69640731 has 6 divisors (see below), whose sum is σ = 100592180. Its totient is φ = 46427148.

The previous prime is 69640723. The next prime is 69640751. The reversal of 69640731 is 13704696.

69640731 is a `hidden beast` number, since 6 + 9 + 640 + 7 + 3 + 1 = 666.

It is not a de Polignac number, because 69640731 - 2³ = 69640723 is a prime.

It is a super-2 number, since 2×69640731² = 9699662828428722, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (69640751) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 3868921 + ... + 3868938.

Almost surely, 2^69640731 is an apocalyptic number.

69640731 is a deficient number, since it is larger than the sum of its proper divisors (30951449).

69640731 is a wasteful number, since it uses less digits than its factorization.

69640731 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7737865 (or 7737862 counting only the distinct ones).

The product of its (nonzero) digits is 27216, while the sum is 36.

The square root of 69640731 is about 8345.1022162703. The cubic root of 69640731 is about 411.4222488384.

The spelling of 69640731 in words is "sixty-nine million, six hundred forty thousand, seven hundred thirty-one".