31693489 has 4 divisors (see below), whose sum is σ = 32020324. Its totient is φ = 31366656.

The previous prime is 31693483. The next prime is 31693511. The reversal of 31693489 is 98439613.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 98439613 = 7243 ⋅13591.

It can be written as a sum of positive squares in 2 ways, for example, as 10349089 + 21344400 = 3217^2 + 4620^2 .

It is a cyclic number.

It is not a de Polignac number, because 31693489 - 2³ = 31693481 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (31693481) 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, 163272 + ... + 163465.

It is an arithmetic number, because the mean of its divisors is an integer number (8005081).

Almost surely, 2^31693489 is an apocalyptic number.

It is an amenable number.

31693489 is a deficient number, since it is larger than the sum of its proper divisors (326835).

31693489 is an equidigital number, since it uses as much as digits as its factorization.

31693489 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 326834.

The product of its digits is 139968, while the sum is 43.

The square root of 31693489 is about 5629.6970611215. The cubic root of 31693489 is about 316.4632985385.

The spelling of 31693489 in words is "thirty-one million, six hundred ninety-three thousand, four hundred eighty-nine".