31997229 has 16 divisors (see below), whose sum is σ = 46738944. Its totient is φ = 19310000.

The previous prime is 31997227. The next prime is 31997233. The reversal of 31997229 is 92279913.

It is a happy number.

It is a cyclic number.

It is not a de Polignac number, because 31997229 - 2¹ = 31997227 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31997221) 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, 6352 + ... + 10214.

It is an arithmetic number, because the mean of its divisors is an integer number (2921184).

Almost surely, 2^31997229 is an apocalyptic number.

It is an amenable number.

31997229 is a deficient number, since it is larger than the sum of its proper divisors (14741715).

31997229 is a wasteful number, since it uses less digits than its factorization.

31997229 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4128.

The product of its digits is 61236, while the sum is 42.

The square root of 31997229 is about 5656.6093200786. The cubic root of 31997229 is about 317.4710461951.

The spelling of 31997229 in words is "thirty-one million, nine hundred ninety-seven thousand, two hundred twenty-nine".