31291016 has 16 divisors (see below), whose sum is σ = 62122140. Its totient is φ = 14725120.

The previous prime is 31291009. The next prime is 31291019. The reversal of 31291016 is 61019213.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 30758116 + 532900 = 5546^2 + 730^2 .

It is a junction number, because it is equal to n+sod(n) for n = 31290982 and 31291000.

It is not an unprimeable number, because it can be changed into a prime (31291019) 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, 114905 + ... + 115176.

Almost surely, 2^31291016 is an apocalyptic number.

It is an amenable number.

31291016 is a deficient number, since it is larger than the sum of its proper divisors (30831124).

31291016 is a wasteful number, since it uses less digits than its factorization.

31291016 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 230104 (or 230100 counting only the distinct ones).

The product of its (nonzero) digits is 324, while the sum is 23.

The square root of 31291016 is about 5593.8373233407. The cubic root of 31291016 is about 315.1180073521.

The spelling of 31291016 in words is "thirty-one million, two hundred ninety-one thousand, sixteen".