31213142 has 4 divisors (see below), whose sum is σ = 46819716. Its totient is φ = 15606570.

The previous prime is 31213129. The next prime is 31213157. The reversal of 31213142 is 24131213.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 24131213 = 43 ⋅561191.

It is a self number, because there is not a number n which added to its sum of digits gives 31213142.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 7803284 + ... + 7803287.

It is an arithmetic number, because the mean of its divisors is an integer number (11704929).

Almost surely, 2^31213142 is an apocalyptic number.

31213142 is a deficient number, since it is larger than the sum of its proper divisors (15606574).

31213142 is a wasteful number, since it uses less digits than its factorization.

31213142 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15606573.

The product of its digits is 144, while the sum is 17.

The square root of 31213142 is about 5586.8722913630. The cubic root of 31213142 is about 314.8563786356.

Adding to 31213142 its reverse (24131213), we get a palindrome (55344355).

The spelling of 31213142 in words is "thirty-one million, two hundred thirteen thousand, one hundred forty-two".