21010101011020 has 96 divisors (see below), whose sum is σ = 48167733067776. Its totient is φ = 7634404051200.

The previous prime is 21010101010963. The next prime is 21010101011021. The reversal of 21010101011020 is 2011010101012.

It is a super-2 number, since 2×21010101011020² (a number of 27 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (10).

It is a junction number, because it is equal to n+sod(n) for n = 21010101010988 and 21010101011006.

It is not an unprimeable number, because it can be changed into a prime (21010101011021) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 2331084034 + ... + 2331093046.

It is an arithmetic number, because the mean of its divisors is an integer number (501747219456).

Almost surely, 2^{21010101011020} is an apocalyptic number.

21010101011020 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21010101011020 is an abundant number, since it is smaller than the sum of its proper divisors (27157632056756).

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

21010101011020 is a wasteful number, since it uses less digits than its factorization.

21010101011020 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15671 (or 15669 counting only the distinct ones).

The product of its (nonzero) digits is 4, while the sum is 10.

Adding to 21010101011020 its reverse (2011010101012), we get a palindrome (23021111112032).

The spelling of 21010101011020 in words is "twenty-one trillion, ten billion, one hundred one million, eleven thousand, twenty".