31308642 has 24 divisors (see below), whose sum is σ = 68290560. Its totient is φ = 10366200.

The previous prime is 31308617. The next prime is 31308643. The reversal of 31308642 is 24680313.

It is a happy number.

31308642 is a `hidden beast` number, since 3 + 13 + 0 + 8 + 642 = 666.

It is not an unprimeable number, because it can be changed into a prime (31308643) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 3042 + ... + 8477.

It is an arithmetic number, because the mean of its divisors is an integer number (2845440).

Almost surely, 2^31308642 is an apocalyptic number.

31308642 is an abundant number, since it is smaller than the sum of its proper divisors (36981918).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

31308642 is a wasteful number, since it uses less digits than its factorization.

31308642 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11678 (or 11675 counting only the distinct ones).

The product of its (nonzero) digits is 3456, while the sum is 27.

The square root of 31308642 is about 5595.4125853238. The cubic root of 31308642 is about 315.1771641340.

Adding to 31308642 its reverse (24680313), we get a palindrome (55988955).

The spelling of 31308642 in words is "thirty-one million, three hundred eight thousand, six hundred forty-two".