27661616640 has 1600 divisors, whose sum is σ = 128338214400. Its totient is φ = 5541986304.

The previous prime is 27661616639. The next prime is 27661616669. The reversal of 27661616640 is 4661616672.

27661616640 is a `hidden beast` number, since 27 + 6 + 6 + 1 + 616 + 6 + 4 + 0 = 666.

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 polite number, since it can be written in 159 ways as a sum of consecutive naturals, for example, 468840931 + ... + 468840989.

It is an arithmetic number, because the mean of its divisors is an integer number (80211384).

Almost surely, 2^27661616640 is an apocalyptic number.

27661616640 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 27661616640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (64169107200).

27661616640 is an abundant number, since it is smaller than the sum of its proper divisors (100676597760).

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

27661616640 is a wasteful number, since it uses less digits than its factorization.

27661616640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 137 (or 112 counting only the distinct ones).

The product of its (nonzero) digits is 435456, while the sum is 45.

The spelling of 27661616640 in words is "twenty-seven billion, six hundred sixty-one million, six hundred sixteen thousand, six hundred forty".