31609641 has 16 divisors (see below), whose sum is σ = 48333824. Its totient is φ = 18000144.

The previous prime is 31609631. The next prime is 31609661. The reversal of 31609641 is 14690613.

It is not a de Polignac number, because 31609641 - 2⁵ = 31609609 is a prime.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 31609599 and 31609608.

It is not an unprimeable number, because it can be changed into a prime (31609631) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 3996 + ... + 8898.

It is an arithmetic number, because the mean of its divisors is an integer number (3020864).

Almost surely, 2^31609641 is an apocalyptic number.

It is an amenable number.

31609641 is a deficient number, since it is larger than the sum of its proper divisors (16724183).

31609641 is a wasteful number, since it uses less digits than its factorization.

31609641 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5220.

The product of its (nonzero) digits is 3888, while the sum is 30.

The square root of 31609641 is about 5622.2451920919. The cubic root of 31609641 is about 316.1839746139.

The spelling of 31609641 in words is "thirty-one million, six hundred nine thousand, six hundred forty-one".