13640731 has 8 divisors (see below), whose sum is σ = 14910224. Its totient is φ = 12402720.

The previous prime is 13640723. The next prime is 13640743. The reversal of 13640731 is 13704631.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 13640731 - 2³ = 13640723 is a prime.

It is a super-2 number, since 2×13640731² = 372139084428722, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 13640696 and 13640705.

It is not an unprimeable number, because it can be changed into a prime (13640791) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 6960 + ... + 8701.

It is an arithmetic number, because the mean of its divisors is an integer number (1863778).

Almost surely, 2^13640731 is an apocalyptic number.

13640731 is a deficient number, since it is larger than the sum of its proper divisors (1269493).

13640731 is a wasteful number, since it uses less digits than its factorization.

13640731 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15741.

The product of its (nonzero) digits is 1512, while the sum is 25.

The square root of 13640731 is about 3693.3360258715. The cubic root of 13640731 is about 238.9346938508.

The spelling of 13640731 in words is "thirteen million, six hundred forty thousand, seven hundred thirty-one".