981135720 has 64 divisors (see below), whose sum is σ = 3270456000. Its totient is φ = 261635904.

The previous prime is 981135707. The next prime is 981135731. The reversal of 981135720 is 27531189.

981135720 is a `hidden beast` number, since 9 + 81 + 1 + 3 + 572 + 0 = 666.

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

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 15 ways as a sum of consecutive naturals, for example, 453150 + ... + 455309.

It is an arithmetic number, because the mean of its divisors is an integer number (51100875).

Almost surely, 2^981135720 is an apocalyptic number.

981135720 is a gapful number since it is divisible by the number (90) formed by its first and last digit.

It is an amenable number.

981135720 is an abundant number, since it is smaller than the sum of its proper divisors (2289320280).

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

981135720 is a wasteful number, since it uses less digits than its factorization.

981135720 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 908479 (or 908469 counting only the distinct ones).

The product of its (nonzero) digits is 15120, while the sum is 36.

The square root of 981135720 is about 31323.0860548574. The cubic root of 981135720 is about 993.6719468777.

The spelling of 981135720 in words is "nine hundred eighty-one million, one hundred thirty-five thousand, seven hundred twenty".