31263132720 has 80 divisors (see below), whose sum is σ = 101129455872. Its totient is φ = 7974362880.

The previous prime is 31263132661. The next prime is 31263132727. The reversal of 31263132720 is 2723136213.

It is a tau number, because it is divible by the number of its divisors (80).

It is a Harshad number since it is a multiple of its sum of digits (30).

It is not an unprimeable number, because it can be changed into a prime (31263132727) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2826286 + ... + 2837325.

Almost surely, 2^31263132720 is an apocalyptic number.

31263132720 is a gapful number since it is divisible by the number (30) formed by its first and last digit.

It is an amenable number.

31263132720 is an abundant number, since it is smaller than the sum of its proper divisors (69866323152).

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

31263132720 is a wasteful number, since it uses less digits than its factorization.

31263132720 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5663650 (or 5663644 counting only the distinct ones).

The product of its (nonzero) digits is 9072, while the sum is 30.

Adding to 31263132720 its reverse (2723136213), we get a palindrome (33986268933).

The spelling of 31263132720 in words is "thirty-one billion, two hundred sixty-three million, one hundred thirty-two thousand, seven hundred twenty".