27721612800 has 720 divisors, whose sum is σ = 118436638320. Its totient is φ = 6332497920.

The previous prime is 27721612771. The next prime is 27721612801. The reversal of 27721612800 is 821612772.

It is a tau number, because it is divible by the number of its divisors (720).

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 (27721612801) by changing a digit.

It is a polite number, since it can be written in 71 ways as a sum of consecutive naturals, for example, 16933582 + ... + 16935218.

It is an arithmetic number, because the mean of its divisors is an integer number (164495331).

Almost surely, 2^27721612800 is an apocalyptic number.

27721612800 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 27721612800, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (59218319160).

27721612800 is an abundant number, since it is smaller than the sum of its proper divisors (90715025520).

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

27721612800 is a wasteful number, since it uses less digits than its factorization.

27721612800 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1688 (or 1654 counting only the distinct ones).

The product of its (nonzero) digits is 18816, while the sum is 36.

The spelling of 27721612800 in words is "twenty-seven billion, seven hundred twenty-one million, six hundred twelve thousand, eight hundred".