31231020020 has 48 divisors (see below), whose sum is σ = 66471417936. Its totient is φ = 12324480000.

The previous prime is 31231019987. The next prime is 31231020131. The reversal of 31231020020 is 2002013213.

It is a happy number.

It can be written as a sum of positive squares in 8 ways, for example, as 1197436816 + 30033583204 = 34604^2 + 173302^2 .

It is a super-2 number, since 2×31231020020² (a number of 22 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 31231019977 and 31231020004.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 540110 + ... + 595130.

It is an arithmetic number, because the mean of its divisors is an integer number (1384821207).

Almost surely, 2^31231020020 is an apocalyptic number.

It is an amenable number.

31231020020 is an abundant number, since it is smaller than the sum of its proper divisors (35240397916).

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

31231020020 is a wasteful number, since it uses less digits than its factorization.

31231020020 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 55412 (or 55410 counting only the distinct ones).

The product of its (nonzero) digits is 72, while the sum is 14.

Adding to 31231020020 its reverse (2002013213), we get a palindrome (33233033233).

The spelling of 31231020020 in words is "thirty-one billion, two hundred thirty-one million, twenty thousand, twenty".