21210012016020 has 72 divisors (see below), whose sum is σ = 64389047663304. Its totient is φ = 5651430789888.

The previous prime is 21210012016019. The next prime is 21210012016021. The reversal of 21210012016020 is 2061021001212.

21210012016020 is a `hidden beast` number, since 21 + 21 + 0 + 0 + 1 + 20 + 1 + 602 + 0 = 666.

It is an interprime number because it is at equal distance from previous prime (21210012016019) and next prime (21210012016021).

It can be written as a sum of positive squares in 4 ways, for example, as 2985548559876 + 18224463456144 = 1727874^2 + 4269012^2 .

It is a super-3 number, since 3×21210012016020³ (a number of 41 digits) contains 333 as substring.

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a junction number, because it is equal to n+sod(n) for n = 21210012015984 and 21210012016002.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21210012016021) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 47406039 + ... + 47851358.

It is an arithmetic number, because the mean of its divisors is an integer number (894292328657).

Almost surely, 2^{21210012016020} is an apocalyptic number.

21210012016020 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21210012016020 is an abundant number, since it is smaller than the sum of its proper divisors (43179035647284).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21210012016020 is a wasteful number, since it uses less digits than its factorization.

21210012016020 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 95258649 (or 95258644 counting only the distinct ones).

The product of its (nonzero) digits is 96, while the sum is 18.

Adding to 21210012016020 its reverse (2061021001212), we get a palindrome (23271033017232).

The spelling of 21210012016020 in words is "twenty-one trillion, two hundred ten billion, twelve million, sixteen thousand, twenty".