210120010020 has 72 divisors (see below), whose sum is σ = 639539494776. Its totient is φ = 55840753152.

The previous prime is 210120010019. The next prime is 210120010057. The reversal of 210120010020 is 20010021012.

It can be written as a sum of positive squares in 4 ways, for example, as 86969548836 + 123150461184 = 294906^2 + 350928^2 .

It is a super-2 number, since 2×210120010020² (a number of 23 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (9).

It is a junction number, because it is equal to n+sod(n) for n = 210120009984 and 210120010011.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 1939297 + ... + 2044776.

It is an arithmetic number, because the mean of its divisors is an integer number (8882492983).

Almost surely, 2^210120010020 is an apocalyptic number.

210120010020 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

210120010020 is an abundant number, since it is smaller than the sum of its proper divisors (429419484756).

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

210120010020 is a wasteful number, since it uses less digits than its factorization.

210120010020 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3984381 (or 3984376 counting only the distinct ones).

The product of its (nonzero) digits is 8, while the sum is 9.

Adding to 210120010020 its reverse (20010021012), we get a palindrome (230130031032).

The spelling of 210120010020 in words is "two hundred ten billion, one hundred twenty million, ten thousand, twenty".