77555511840 has 48 divisors (see below), whose sum is σ = 244299863808. Its totient is φ = 20681469696.

The previous prime is 77555511833. The next prime is 77555511907. The reversal of 77555511840 is 4811555577.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (48).

It is a Harshad number since it is a multiple of its sum of digits (48).

It is a self number, because there is not a number n which added to its sum of digits gives 77555511840.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 80786512 + ... + 80787471.

It is an arithmetic number, because the mean of its divisors is an integer number (5089580496).

Almost surely, 2^77555511840 is an apocalyptic number.

It is an amenable number.

77555511840 is an abundant number, since it is smaller than the sum of its proper divisors (166744351968).

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

77555511840 is a wasteful number, since it uses less digits than its factorization.

77555511840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 161574001 (or 161573993 counting only the distinct ones).

The product of its (nonzero) digits is 980000, while the sum is 48.

The spelling of 77555511840 in words is "seventy-seven billion, five hundred fifty-five million, five hundred eleven thousand, eight hundred forty".