31422440 has 32 divisors (see below), whose sum is σ = 80801280. Its totient is φ = 10773312.

The previous prime is 31422403. The next prime is 31422463. The reversal of 31422440 is 4422413.

It is a Harshad number since it is a multiple of its sum of digits (20).

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 55832 + ... + 56391.

It is an arithmetic number, because the mean of its divisors is an integer number (2525040).

Almost surely, 2^31422440 is an apocalyptic number.

It is an amenable number.

31422440 is an abundant number, since it is smaller than the sum of its proper divisors (49378840).

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

31422440 is a wasteful number, since it uses less digits than its factorization.

31422440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 112241 (or 112237 counting only the distinct ones).

The product of its (nonzero) digits is 768, while the sum is 20.

The square root of 31422440 is about 5605.5722277034. The cubic root of 31422440 is about 315.5585621687.

Adding to 31422440 its reverse (4422413), we get a palindrome (35844853).

The spelling of 31422440 in words is "thirty-one million, four hundred twenty-two thousand, four hundred forty".