21001021012122 has 32 divisors (see below), whose sum is σ = 42795530461440. Its totient is φ = 6868098419520.

The previous prime is 21001021012051. The next prime is 21001021012157. The reversal of 21001021012122 is 22121012010012.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 13304847 + ... + 14799357.

It is an arithmetic number, because the mean of its divisors is an integer number (1337360326920).

Almost surely, 2^{21001021012122} is an apocalyptic number.

21001021012122 is an abundant number, since it is smaller than the sum of its proper divisors (21794509449318).

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

21001021012122 is a wasteful number, since it uses less digits than its factorization.

21001021012122 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1538758.

The product of its (nonzero) digits is 32, while the sum is 15.

Adding to 21001021012122 its reverse (22121012010012), we get a palindrome (43122033022134).

The spelling of 21001021012122 in words is "twenty-one trillion, one billion, twenty-one million, twelve thousand, one hundred twenty-two".