30987991280 has 80 divisors (see below), whose sum is σ = 73901159904. Its totient is φ = 12077614080.

The previous prime is 30987991273. The next prime is 30987991297. The reversal of 30987991280 is 8219978903.

It is a tau number, because it is divible by the number of its divisors (80).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1437542 + ... + 1458938.

Almost surely, 2^30987991280 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 30987991280, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (36950579952).

30987991280 is an abundant number, since it is smaller than the sum of its proper divisors (42913168624).

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

30987991280 is a wasteful number, since it uses less digits than its factorization.

30987991280 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 21874 (or 21868 counting only the distinct ones).

The product of its (nonzero) digits is 1959552, while the sum is 56.

The spelling of 30987991280 in words is "thirty billion, nine hundred eighty-seven million, nine hundred ninety-one thousand, two hundred eighty".