27721958400 has 660 divisors, whose sum is σ = 106421196420. Its totient is φ = 7122124800.

The previous prime is 27721958387. The next prime is 27721958437. The reversal of 27721958400 is 485912772.

It is a happy number.

27721958400 is a `hidden beast` number, since 27 + 7 + 219 + 5 + 8 + 400 = 666.

It can be written as a sum of positive squares in 6 ways, for example, as 1337803776 + 26384154624 = 36576^2 + 162432^2 .

It is a Harshad number since it is a multiple of its sum of digits (45).

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 59 ways as a sum of consecutive naturals, for example, 60134170 + ... + 60134630.

It is an arithmetic number, because the mean of its divisors is an integer number (161244237).

Almost surely, 2^27721958400 is an apocalyptic number.

27721958400 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 27721958400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (53210598210).

27721958400 is an abundant number, since it is smaller than the sum of its proper divisors (78699238020).

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

27721958400 is a wasteful number, since it uses less digits than its factorization.

27721958400 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 532 (or 500 counting only the distinct ones).

The product of its (nonzero) digits is 282240, while the sum is 45.

The spelling of 27721958400 in words is "twenty-seven billion, seven hundred twenty-one million, nine hundred fifty-eight thousand, four hundred".