31142304 has 72 divisors (see below), whose sum is σ = 89867232. Its totient is φ = 10227840.

The previous prime is 31142303. The next prime is 31142381. The reversal of 31142304 is 40324113.

It is a tau number, because it is divible by the number of its divisors (72).

It is a Harshad number since it is a multiple of its sum of digits (18).

It is not an unprimeable number, because it can be changed into a prime (31142303) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 19687 + ... + 21209.

It is an arithmetic number, because the mean of its divisors is an integer number (1248156).

Almost surely, 2^31142304 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 31142304, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (44933616).

31142304 is an abundant number, since it is smaller than the sum of its proper divisors (58724928).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

31142304 is a wasteful number, since it uses less digits than its factorization.

31142304 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1610 (or 1599 counting only the distinct ones).

The product of its (nonzero) digits is 288, while the sum is 18.

The square root of 31142304 is about 5580.5290071820. The cubic root of 31142304 is about 314.6180101281.

Adding to 31142304 its reverse (40324113), we get a palindrome (71466417).

The spelling of 31142304 in words is "thirty-one million, one hundred forty-two thousand, three hundred four".