20040013521 has 32 divisors (see below), whose sum is σ = 33504739200. Its totient is φ = 11726648640.

The previous prime is 20040013517. The next prime is 20040013537. The reversal of 20040013521 is 12531004002.

20040013521 is a `hidden beast` number, since 200 + 400 + 13 + 52 + 1 = 666.

It is not a de Polignac number, because 20040013521 - 2² = 20040013517 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 20040013494 and 20040013503.

It is not an unprimeable number, because it can be changed into a prime (20040013541) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 1154746 + ... + 1171971.

It is an arithmetic number, because the mean of its divisors is an integer number (1047023100).

Almost surely, 2^20040013521 is an apocalyptic number.

It is an amenable number.

20040013521 is a deficient number, since it is larger than the sum of its proper divisors (13464725679).

20040013521 is a wasteful number, since it uses less digits than its factorization.

20040013521 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2326766 (or 2326760 counting only the distinct ones).

The product of its (nonzero) digits is 240, while the sum is 18.

Adding to 20040013521 its reverse (12531004002), we get a palindrome (32571017523).

The spelling of 20040013521 in words is "twenty billion, forty million, thirteen thousand, five hundred twenty-one".