21001011122020 has 48 divisors (see below), whose sum is σ = 44279417060928. Its totient is φ = 8366636624000.

The previous prime is 21001011121969. The next prime is 21001011122023. The reversal of 21001011122020 is 2022111010012.

It is a super-3 number, since 3×21001011122020³ (a number of 41 digits) contains 333 as substring.

It is not an unprimeable number, because it can be changed into a prime (21001011122023) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 185748747 + ... + 185861773.

It is an arithmetic number, because the mean of its divisors is an integer number (922487855436).

Almost surely, 2^{21001011122020} is an apocalyptic number.

21001011122020 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21001011122020 is an abundant number, since it is smaller than the sum of its proper divisors (23278405938908).

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

21001011122020 is a wasteful number, since it uses less digits than its factorization.

21001011122020 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 150300 (or 150298 counting only the distinct ones).

The product of its (nonzero) digits is 16, while the sum is 13.

Adding to 21001011122020 its reverse (2022111010012), we get a palindrome (23023122132032).

The spelling of 21001011122020 in words is "twenty-one trillion, one billion, eleven million, one hundred twenty-two thousand, twenty".