31130021020 has 48 divisors (see below), whose sum is σ = 74722108608. Its totient is φ = 10671713280.

The previous prime is 31130021017. The next prime is 31130021023. The reversal of 31130021020 is 2012003113.

It is an interprime number because it is at equal distance from previous prime (31130021017) and next prime (31130021023).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31130021023) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1907214 + ... + 1923466.

It is an arithmetic number, because the mean of its divisors is an integer number (1556710596).

Almost surely, 2^31130021020 is an apocalyptic number.

It is an amenable number.

31130021020 is an abundant number, since it is smaller than the sum of its proper divisors (43592087588).

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

31130021020 is a wasteful number, since it uses less digits than its factorization.

31130021020 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 29950 (or 29948 counting only the distinct ones).

The product of its (nonzero) digits is 36, while the sum is 13.

Adding to 31130021020 its reverse (2012003113), we get a palindrome (33142024133).

The spelling of 31130021020 in words is "thirty-one billion, one hundred thirty million, twenty-one thousand, twenty".