30991002720 has 96 divisors (see below), whose sum is σ = 103364136288. Its totient is φ = 7778131968.

The previous prime is 30991002701. The next prime is 30991002727. The reversal of 30991002720 is 2720019903.

It is a tau number, because it is divible by the number of its divisors (96).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (30991002727) by changing a digit.

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, 1890799 + ... + 1907118.

It is an arithmetic number, because the mean of its divisors is an integer number (1076709753).

Almost surely, 2^30991002720 is an apocalyptic number.

30991002720 is a gapful number since it is divisible by the number (30) formed by its first and last digit.

It is an amenable number.

30991002720 is an abundant number, since it is smaller than the sum of its proper divisors (72373133568).

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

30991002720 is a wasteful number, since it uses less digits than its factorization.

30991002720 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3797952 (or 3797944 counting only the distinct ones).

The product of its (nonzero) digits is 6804, while the sum is 33.

The spelling of 30991002720 in words is "thirty billion, nine hundred ninety-one million, two thousand, seven hundred twenty".