31081397760 has 1600 divisors, whose sum is σ = 142598016000. Its totient is φ = 6437781504.

The previous prime is 31081397717. The next prime is 31081397777. The reversal of 31081397760 is 6779318013.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 159 ways as a sum of consecutive naturals, for example, 1351365109 + ... + 1351365131.

It is an arithmetic number, because the mean of its divisors is an integer number (89123760).

Almost surely, 2^31081397760 is an apocalyptic number.

31081397760 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 31081397760, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (71299008000).

31081397760 is an abundant number, since it is smaller than the sum of its proper divisors (111516618240).

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

31081397760 is an equidigital number, since it uses as much as digits as its factorization.

31081397760 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 98 (or 59 counting only the distinct ones).

The product of its (nonzero) digits is 190512, while the sum is 45.

The spelling of 31081397760 in words is "thirty-one billion, eighty-one million, three hundred ninety-seven thousand, seven hundred sixty".