21050522121 has 8 divisors (see below), whose sum is σ = 28068206400. Its totient is φ = 14033259632.

The previous prime is 21050522113. The next prime is 21050522173. The reversal of 21050522121 is 12122505012.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 21050522121 - 2³ = 21050522113 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21050522321) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 39451 + ... + 208943.

It is an arithmetic number, because the mean of its divisors is an integer number (3508525800).

Almost surely, 2^21050522121 is an apocalyptic number.

It is an amenable number.

21050522121 is a deficient number, since it is larger than the sum of its proper divisors (7017684279).

21050522121 is a wasteful number, since it uses less digits than its factorization.

21050522121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 210895.

The product of its (nonzero) digits is 400, while the sum is 21.

The spelling of 21050522121 in words is "twenty-one billion, fifty million, five hundred twenty-two thousand, one hundred twenty-one".