21004511121 has 36 divisors (see below), whose sum is σ = 33457920496. Its totient is φ = 12688338960.

The previous prime is 21004511119. The next prime is 21004511137. The reversal of 21004511121 is 12111540012.

21004511121 is a `hidden beast` number, since 2 + 100 + 451 + 112 + 1 = 666.

It is not a de Polignac number, because 21004511121 - 2¹ = 21004511119 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21004511094 and 21004511103.

It is not an unprimeable number, because it can be changed into a prime (21004511821) by changing a digit.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 302910 + ... + 365736.

Almost surely, 2^21004511121 is an apocalyptic number.

It is an amenable number.

21004511121 is a deficient number, since it is larger than the sum of its proper divisors (12453409375).

21004511121 is a wasteful number, since it uses less digits than its factorization.

21004511121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 63162 (or 63148 counting only the distinct ones).

The product of its (nonzero) digits is 80, while the sum is 18.

The spelling of 21004511121 in words is "twenty-one billion, four million, five hundred eleven thousand, one hundred twenty-one".