31481781120 has 384 divisors, whose sum is σ = 112475563200. Its totient is φ = 8108605440.

The previous prime is 31481781119. The next prime is 31481781127. The reversal of 31481781120 is 2118718413.

It is a tau number, because it is divible by the number of its divisors (384).

It is a super-2 number, since 2×31481781120² (a number of 22 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31481781127) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 25740829 + ... + 25742051.

Almost surely, 2^31481781120 is an apocalyptic number.

31481781120 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 31481781120, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (56237781600).

31481781120 is an abundant number, since it is smaller than the sum of its proper divisors (80993782080).

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

31481781120 is a wasteful number, since it uses less digits than its factorization.

31481781120 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1398 (or 1383 counting only the distinct ones).

The product of its (nonzero) digits is 10752, while the sum is 36.

The spelling of 31481781120 in words is "thirty-one billion, four hundred eighty-one million, seven hundred eighty-one thousand, one hundred twenty".