31220000020 has 24 divisors (see below), whose sum is σ = 71522182368. Its totient is φ = 11352727200.

The previous prime is 31219999981. The next prime is 31220000023. The reversal of 31220000020 is 2000002213.

It is a Harshad number since it is a multiple of its sum of digits (10).

It is a junction number, because it is equal to n+sod(n) for n = 31219999961 and 31220000006.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31220000023) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 70954326 + ... + 70954765.

It is an arithmetic number, because the mean of its divisors is an integer number (2980090932).

Almost surely, 2^31220000020 is an apocalyptic number.

It is an amenable number.

31220000020 is an abundant number, since it is smaller than the sum of its proper divisors (40302182348).

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

31220000020 is a wasteful number, since it uses less digits than its factorization.

31220000020 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 141909111 (or 141909109 counting only the distinct ones).

The product of its (nonzero) digits is 24, while the sum is 10.

Adding to 31220000020 its reverse (2000002213), we get a palindrome (33220002233).

The spelling of 31220000020 in words is "thirty-one billion, two hundred twenty million, twenty", and thus it is an aban number.