31661339 has 4 divisors (see below), whose sum is σ = 31951920. Its totient is φ = 31370760.

The previous prime is 31661309. The next prime is 31661351. The reversal of 31661339 is 93316613.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 93316613 = 13 ⋅7178201.

It is a cyclic number.

It is not a de Polignac number, because 31661339 - 2⁸ = 31661083 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (31661309) 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, 145127 + ... + 145344.

It is an arithmetic number, because the mean of its divisors is an integer number (7987980).

Almost surely, 2^31661339 is an apocalyptic number.

31661339 is a deficient number, since it is larger than the sum of its proper divisors (290581).

31661339 is a wasteful number, since it uses less digits than its factorization.

31661339 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 290580.

The product of its digits is 8748, while the sum is 32.

The square root of 31661339 is about 5626.8409431936. The cubic root of 31661339 is about 316.3562551300.

The spelling of 31661339 in words is "thirty-one million, six hundred sixty-one thousand, three hundred thirty-nine".