27989251920 has 400 divisors, whose sum is σ = 111488602368. Its totient is φ = 6375075840.

The previous prime is 27989251919. The next prime is 27989251967. The reversal of 27989251920 is 2915298972.

27989251920 is a `hidden beast` number, since 27 + 9 + 89 + 2 + 519 + 20 = 666.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 79 ways as a sum of consecutive naturals, for example, 15285405 + ... + 15287235.

Almost surely, 2^27989251920 is an apocalyptic number.

27989251920 is a gapful number since it is divisible by the number (20) 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 27989251920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (55744301184).

27989251920 is an abundant number, since it is smaller than the sum of its proper divisors (83499350448).

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

27989251920 is a wasteful number, since it uses less digits than its factorization.

27989251920 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2200 (or 2185 counting only the distinct ones).

The product of its (nonzero) digits is 1632960, while the sum is 54.

The spelling of 27989251920 in words is "twenty-seven billion, nine hundred eighty-nine million, two hundred fifty-one thousand, nine hundred twenty".