31730913 has 8 divisors (see below), whose sum is σ = 47008800. Its totient is φ = 21153924.

The previous prime is 31730899. The next prime is 31730917. The reversal of 31730913 is 31903713.

It is not a de Polignac number, because 31730913 - 2¹⁰ = 31729889 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (27), and also a Moran number because the ratio is a prime number: 1175219 = 31730913 / (3 + 1 + 7 + 3 + 0 + 9 + 1 + 3).

It is not an unprimeable number, because it can be changed into a prime (31730917) 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, 587583 + ... + 587636.

It is an arithmetic number, because the mean of its divisors is an integer number (5876100).

Almost surely, 2^31730913 is an apocalyptic number.

It is an amenable number.

31730913 is a deficient number, since it is larger than the sum of its proper divisors (15277887).

31730913 is a wasteful number, since it uses less digits than its factorization.

31730913 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1175228 (or 1175222 counting only the distinct ones).

The product of its (nonzero) digits is 1701, while the sum is 27.

The square root of 31730913 is about 5633.0198827982. The cubic root of 31730913 is about 316.5878105896.

The spelling of 31730913 in words is "thirty-one million, seven hundred thirty thousand, nine hundred thirteen".