213307720731 has 80 divisors (see below), whose sum is σ = 368416401408. Its totient is φ = 120471624000.

The previous prime is 213307720697. The next prime is 213307720733. The reversal of 213307720731 is 137027703312.

213307720731 is a `hidden beast` number, since 21 + 330 + 77 + 207 + 31 = 666.

It is not a de Polignac number, because 213307720731 - 2¹⁵ = 213307687963 is a prime.

It is a super-2 number, since 2×213307720731² (a number of 23 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (213307720733) by changing a digit.

It is a polite number, since it can be written in 79 ways as a sum of consecutive naturals, for example, 36132526 + ... + 36138428.

Almost surely, 2^213307720731 is an apocalyptic number.

213307720731 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

213307720731 is a deficient number, since it is larger than the sum of its proper divisors (155108680677).

213307720731 is a wasteful number, since it uses less digits than its factorization.

213307720731 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6654 (or 6645 counting only the distinct ones).

The product of its (nonzero) digits is 37044, while the sum is 36.

The spelling of 213307720731 in words is "two hundred thirteen billion, three hundred seven million, seven hundred twenty thousand, seven hundred thirty-one".