31311042420 has 96 divisors (see below), whose sum is σ = 100396800000. Its totient is φ = 7142419584.

The previous prime is 31311042383. The next prime is 31311042431. The reversal of 31311042420 is 2424011313.

It is a Harshad number since it is a multiple of its sum of digits (21).

It is a congruent number.

It is an unprimeable number.

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 31 ways as a sum of consecutive naturals, for example, 134881 + ... + 284279.

It is an arithmetic number, because the mean of its divisors is an integer number (1045800000).

Almost surely, 2^31311042420 is an apocalyptic number.

31311042420 is a gapful number since it is divisible by the number (30) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 31311042420, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (50198400000).

31311042420 is an abundant number, since it is smaller than the sum of its proper divisors (69085757580).

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

31311042420 is a wasteful number, since it uses less digits than its factorization.

31311042420 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 149917 (or 149915 counting only the distinct ones).

The product of its (nonzero) digits is 576, while the sum is 21.

Adding to 31311042420 its reverse (2424011313), we get a palindrome (33735053733).

The spelling of 31311042420 in words is "thirty-one billion, three hundred eleven million, forty-two thousand, four hundred twenty".