31123202020 has 24 divisors (see below), whose sum is σ = 65487151800. Its totient is φ = 12424818432.

The previous prime is 31123201957. The next prime is 31123202021. The reversal of 31123202020 is 2020232113.

It can be written as a sum of positive squares in 4 ways, for example, as 3719048256 + 27404153764 = 60984^2 + 165542^2 .

It is a junction number, because it is equal to n+sod(n) for n = 31123201985 and 31123202003.

It is not an unprimeable number, because it can be changed into a prime (31123202021) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1518465 + ... + 1538824.

It is an arithmetic number, because the mean of its divisors is an integer number (2728631325).

Almost surely, 2^31123202020 is an apocalyptic number.

It is an amenable number.

31123202020 is an abundant number, since it is smaller than the sum of its proper divisors (34363949780).

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

31123202020 is a wasteful number, since it uses less digits than its factorization.

31123202020 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3057807 (or 3057805 counting only the distinct ones).

The product of its (nonzero) digits is 144, while the sum is 16.

Adding to 31123202020 its reverse (2020232113), we get a palindrome (33143434133).

The spelling of 31123202020 in words is "thirty-one billion, one hundred twenty-three million, two hundred two thousand, twenty".