61977324864 has 896 divisors, whose sum is σ = 226520727552. Its totient is φ = 14491975680.

The previous prime is 61977324853. The next prime is 61977324869. The reversal of 61977324864 is 46842377916.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (61977324869) by changing a digit.

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 127 ways as a sum of consecutive naturals, for example, 488010369 + ... + 488010495.

It is an arithmetic number, because the mean of its divisors is an integer number (252813312).

Almost surely, 2^61977324864 is an apocalyptic number.

61977324864 is a gapful number since it is divisible by the number (64) 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 61977324864, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (113260363776).

61977324864 is an abundant number, since it is smaller than the sum of its proper divisors (164543402688).

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

61977324864 is a wasteful number, since it uses less digits than its factorization.

61977324864 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 263 (or 253 counting only the distinct ones).

The product of its digits is 12192768, while the sum is 57.

The spelling of 61977324864 in words is "sixty-one billion, nine hundred seventy-seven million, three hundred twenty-four thousand, eight hundred sixty-four".