31906 has 16 divisors (see below), whose sum is σ = 57024. Its totient is φ = 13104.

The previous prime is 31891. The next prime is 31907. The reversal of 31906 is 60913.

31906 is a Rhonda number in base 16.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31907) by changing a digit.

31906 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 576 + ... + 628.

It is an arithmetic number, because the mean of its divisors is an integer number (3564).

2³¹⁹⁰⁶ is an apocalyptic number.

31906 is a deficient number, since it is larger than the sum of its proper divisors (25118).

31906 is a wasteful number, since it uses less digits than its factorization.

31906 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 105.

The product of its (nonzero) digits is 162, while the sum is 19.

The square root of 31906 is about 178.6225069805. The cubic root of 31906 is about 31.7169039467.

The spelling of 31906 in words is "thirty-one thousand, nine hundred six".