31320023240 has 64 divisors (see below), whose sum is σ = 77637683520. Its totient is φ = 11276320000.

The previous prime is 31320023237. The next prime is 31320023249. The reversal of 31320023240 is 4232002313.

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

It is not an unprimeable number, because it can be changed into a prime (31320023249) 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, 307946 + ... + 396825.

It is an arithmetic number, because the mean of its divisors is an integer number (1213088805).

Almost surely, 2^31320023240 is an apocalyptic number.

It is an amenable number.

31320023240 is an abundant number, since it is smaller than the sum of its proper divisors (46317660280).

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

31320023240 is a wasteful number, since it uses less digits than its factorization.

31320023240 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 704894 (or 704890 counting only the distinct ones).

The product of its (nonzero) digits is 864, while the sum is 20.

Adding to 31320023240 its reverse (4232002313), we get a palindrome (35552025553).

The spelling of 31320023240 in words is "thirty-one billion, three hundred twenty million, twenty-three thousand, two hundred forty".