13568739821 has 16 divisors (see below), whose sum is σ = 16764996864. Its totient is φ = 10693914624.

The previous prime is 13568739803. The next prime is 13568739823. The reversal of 13568739821 is 12893786531.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-13568739821 is a prime.

It is a super-2 number, since 2×13568739821² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (13568739823) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 266705 + ... + 313478.

It is an arithmetic number, because the mean of its divisors is an integer number (1047812304).

Almost surely, 2^13568739821 is an apocalyptic number.

It is an amenable number.

13568739821 is a deficient number, since it is larger than the sum of its proper divisors (3196257043).

13568739821 is a wasteful number, since it uses less digits than its factorization.

13568739821 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 580460.

The product of its digits is 2177280, while the sum is 53.

The spelling of 13568739821 in words is "thirteen billion, five hundred sixty-eight million, seven hundred thirty-nine thousand, eight hundred twenty-one".