20101121999956 has 24 divisors (see below), whose sum is σ = 35702270120160. Its totient is φ = 9900475724832.

The previous prime is 20101121999947. The next prime is 20101121999989. The reversal of 20101121999956 is 65999912110102.

It is a happy number.

It is a junction number, because it is equal to n+sod(n) for n = 20101121999897 and 20101121999906.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 51274935 + ... + 51665473.

It is an arithmetic number, because the mean of its divisors is an integer number (1487594588340).

Almost surely, 2^{20101121999956} is an apocalyptic number.

It is an amenable number.

20101121999956 is a deficient number, since it is larger than the sum of its proper divisors (15601148120204).

20101121999956 is a wasteful number, since it uses less digits than its factorization.

20101121999956 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 582663 (or 582661 counting only the distinct ones).

The product of its (nonzero) digits is 787320, while the sum is 55.

The spelling of 20101121999956 in words is "twenty trillion, one hundred one billion, one hundred twenty-one million, nine hundred ninety-nine thousand, nine hundred fifty-six".