61664025600 has 264 divisors, whose sum is σ = 226450111920. Its totient is φ = 16443555840.

The previous prime is 61664025587. The next prime is 61664025617. The reversal of 61664025600 is 652046616.

It is a happy number.

61664025600 is a `hidden beast` number, since 6 + 1 + 6 + 6 + 40 + 2 + 5 + 600 = 666.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 646594 + ... + 735806.

Almost surely, 2^61664025600 is an apocalyptic number.

61664025600 is a gapful number since it is divisible by the number (60) 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 61664025600, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (113225055960).

61664025600 is an abundant number, since it is smaller than the sum of its proper divisors (164786086320).

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

61664025600 is a wasteful number, since it uses less digits than its factorization.

61664025600 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 89252 (or 89223 counting only the distinct ones).

The product of its (nonzero) digits is 51840, while the sum is 36.

The spelling of 61664025600 in words is "sixty-one billion, six hundred sixty-four million, twenty-five thousand, six hundred".