31213143 has 36 divisors (see below), whose sum is σ = 51313080. Its totient is φ = 18172512.

The previous prime is 31213129. The next prime is 31213157. The reversal of 31213143 is 34131213.

It is an interprime number because it is at equal distance from previous prime (31213129) and next prime (31213157).

It is not a de Polignac number, because 31213143 - 2⁸ = 31212887 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31213043) by changing a digit.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 41868 + ... + 42606.

Almost surely, 2^31213143 is an apocalyptic number.

31213143 is a deficient number, since it is larger than the sum of its proper divisors (20099937).

31213143 is a wasteful number, since it uses less digits than its factorization.

31213143 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 796 (or 774 counting only the distinct ones).

The product of its digits is 216, while the sum is 18.

The square root of 31213143 is about 5586.8723808585. The cubic root of 31213143 is about 314.8563819980.

Adding to 31213143 its reverse (34131213), we get a palindrome (65344356).

The spelling of 31213143 in words is "thirty-one million, two hundred thirteen thousand, one hundred forty-three".