31640099 has 4 divisors (see below), whose sum is σ = 32237136. Its totient is φ = 31043064.

The previous prime is 31640039. The next prime is 31640129. The reversal of 31640099 is 99004613.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 99004613 = 173 ⋅572281.

It is a cyclic number.

It is not a de Polignac number, because 31640099 - 2⁸ = 31639843 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (31640039) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 298439 + ... + 298544.

It is an arithmetic number, because the mean of its divisors is an integer number (8059284).

Almost surely, 2^31640099 is an apocalyptic number.

31640099 is a deficient number, since it is larger than the sum of its proper divisors (597037).

31640099 is an equidigital number, since it uses as much as digits as its factorization.

31640099 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 597036.

The product of its (nonzero) digits is 5832, while the sum is 32.

The square root of 31640099 is about 5624.9532442501. The cubic root of 31640099 is about 316.2854968045.

The spelling of 31640099 in words is "thirty-one million, six hundred forty thousand, ninety-nine".