31223157 has 16 divisors (see below), whose sum is σ = 47715840. Its totient is φ = 17790192.

The previous prime is 31223141. The next prime is 31223161. The reversal of 31223157 is 75132213.

It is not a de Polignac number, because 31223157 - 2⁴ = 31223141 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31223057) 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, 5998 + ... + 9920.

It is an arithmetic number, because the mean of its divisors is an integer number (2982240).

Almost surely, 2^31223157 is an apocalyptic number.

It is an amenable number.

31223157 is a deficient number, since it is larger than the sum of its proper divisors (16492683).

31223157 is a wasteful number, since it uses less digits than its factorization.

31223157 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4312.

The product of its digits is 1260, while the sum is 24.

The square root of 31223157 is about 5587.7685170379. The cubic root of 31223157 is about 314.8900498100.

The spelling of 31223157 in words is "thirty-one million, two hundred twenty-three thousand, one hundred fifty-seven".