77444421624 has 128 divisors (see below), whose sum is σ = 218510515200. Its totient is φ = 25409790720.

The previous prime is 77444421617. The next prime is 77444421727. The reversal of 77444421624 is 42612444477.

77444421624 is a `hidden beast` number, since 7 + 7 + 44 + 442 + 162 + 4 = 666.

It is a self number, because there is not a number n which added to its sum of digits gives 77444421624.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 8241969 + ... + 8251359.

It is an arithmetic number, because the mean of its divisors is an integer number (1707113400).

Almost surely, 2^77444421624 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 77444421624, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (109255257600).

77444421624 is an abundant number, since it is smaller than the sum of its proper divisors (141066093576).

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

77444421624 is a wasteful number, since it uses less digits than its factorization.

77444421624 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10002 (or 9992 counting only the distinct ones).

The product of its digits is 1204224, while the sum is 45.

The spelling of 77444421624 in words is "seventy-seven billion, four hundred forty-four million, four hundred twenty-one thousand, six hundred twenty-four".