31031143220 has 384 divisors, whose sum is σ = 89181388800. Its totient is φ = 8782963200.

The previous prime is 31031143219. The next prime is 31031143237. The reversal of 31031143220 is 2234113013.

It is a Harshad number since it is a multiple of its sum of digits (20).

It is a junction number, because it is equal to n+sod(n) for n = 31031143192 and 31031143201.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 127 ways as a sum of consecutive naturals, for example, 64782941 + ... + 64783419.

It is an arithmetic number, because the mean of its divisors is an integer number (232243200).

Almost surely, 2^31031143220 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 31031143220, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (44590694400).

31031143220 is an abundant number, since it is smaller than the sum of its proper divisors (58150245580).

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

31031143220 is a wasteful number, since it uses less digits than its factorization.

31031143220 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 619 (or 617 counting only the distinct ones).

The product of its (nonzero) digits is 432, while the sum is 20.

Adding to 31031143220 its reverse (2234113013), we get a palindrome (33265256233).

The spelling of 31031143220 in words is "thirty-one billion, thirty-one million, one hundred forty-three thousand, two hundred twenty".