31997402 has 8 divisors (see below), whose sum is σ = 48021012. Its totient is φ = 15990400.

The previous prime is 31997359. The next prime is 31997423. The reversal of 31997402 is 20479913.

It can be written as a sum of positive squares in 2 ways, for example, as 25999801 + 5997601 = 5099^2 + 2449^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a super-3 number, since 3×31997402³ (a number of 23 digits) contains 333 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3452 + ... + 8712.

Almost surely, 2^31997402 is an apocalyptic number.

31997402 is a deficient number, since it is larger than the sum of its proper divisors (16023610).

31997402 is a wasteful number, since it uses less digits than its factorization.

31997402 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8304.

The product of its (nonzero) digits is 13608, while the sum is 35.

The square root of 31997402 is about 5656.6246119042. The cubic root of 31997402 is about 317.4716183529.

It can be divided in two parts, 3199 and 7402, that added together give a palindrome (10601).

The spelling of 31997402 in words is "thirty-one million, nine hundred ninety-seven thousand, four hundred two".