31021020020 has 24 divisors (see below), whose sum is σ = 65149686504. Its totient is φ = 12407351936.

The previous prime is 31021019983. The next prime is 31021020061. The reversal of 31021020020 is 2002012013.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 1883212816 + 29137807204 = 43396^2 + 170698^2 .

It is a junction number, because it is equal to n+sod(n) for n = 31021019983 and 31021020010.

It is a congruent number.

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, 201254 + ... + 320226.

It is an arithmetic number, because the mean of its divisors is an integer number (2714570271).

Almost surely, 2^31021020020 is an apocalyptic number.

It is an amenable number.

31021020020 is an abundant number, since it is smaller than the sum of its proper divisors (34128666484).

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

31021020020 is a wasteful number, since it uses less digits than its factorization.

31021020020 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 132019 (or 132017 counting only the distinct ones).

The product of its (nonzero) digits is 24, while the sum is 11.

Adding to 31021020020 its reverse (2002012013), we get a palindrome (33023032033).

The spelling of 31021020020 in words is "thirty-one billion, twenty-one million, twenty thousand, twenty".