31442240820 has 144 divisors (see below), whose sum is σ = 93070192320. Its totient is φ = 7930109952.

The previous prime is 31442240783. The next prime is 31442240833. The reversal of 31442240820 is 2804224413.

It is a super-2 number, since 2×31442240820² (a number of 22 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (30).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 24973351 + ... + 24974609.

It is an arithmetic number, because the mean of its divisors is an integer number (646320780).

Almost surely, 2^31442240820 is an apocalyptic number.

31442240820 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 31442240820, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (46535096160).

31442240820 is an abundant number, since it is smaller than the sum of its proper divisors (61627951500).

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

31442240820 is a wasteful number, since it uses less digits than its factorization.

31442240820 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2462 (or 2441 counting only the distinct ones).

The product of its (nonzero) digits is 12288, while the sum is 30.

The spelling of 31442240820 in words is "thirty-one billion, four hundred forty-two million, two hundred forty thousand, eight hundred twenty".