31663121320 has 16 divisors (see below), whose sum is σ = 71242023060. Its totient is φ = 12665248512.

The previous prime is 31663121317. The next prime is 31663121323. The reversal of 31663121320 is 2312136613.

It is an interprime number because it is at equal distance from previous prime (31663121317) and next prime (31663121323).

It can be written as a sum of positive squares in 2 ways, for example, as 27576587844 + 4086533476 = 166062^2 + 63926^2 .

It is not an unprimeable number, because it can be changed into a prime (31663121323) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 395788977 + ... + 395789056.

Almost surely, 2^31663121320 is an apocalyptic number.

It is an amenable number.

31663121320 is an abundant number, since it is smaller than the sum of its proper divisors (39578901740).

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

31663121320 is a wasteful number, since it uses less digits than its factorization.

31663121320 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 791578044 (or 791578040 counting only the distinct ones).

The product of its (nonzero) digits is 3888, while the sum is 28.

Adding to 31663121320 its reverse (2312136613), we get a palindrome (33975257933).

The spelling of 31663121320 in words is "thirty-one billion, six hundred sixty-three million, one hundred twenty-one thousand, three hundred twenty".