77648656155840 has 4032 divisors, whose sum is σ = 361630055195136. Its totient is φ = 15807052800000.

The previous prime is 77648656155821. The next prime is 77648656155883. The reversal of 77648656155840 is 4855165684677.

77648656155840 is a `hidden beast` number, since 7 + 7 + 6 + 4 + 8 + 6 + 5 + 61 + 558 + 4 + 0 = 666.

It is a tau number, because it is divible by the number of its divisors (4032).

It is a super-2 number, since 2×77648656155840² (a number of 29 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (72).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 575 ways as a sum of consecutive naturals, for example, 309357195715 + ... + 309357195965.

It is an arithmetic number, because the mean of its divisors is an integer number (89689993848).

Almost surely, 2^{77648656155840} is an apocalyptic number.

77648656155840 is a gapful number since it is divisible by the number (70) 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 77648656155840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (180815027597568).

77648656155840 is an abundant number, since it is smaller than the sum of its proper divisors (283981399039296).

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

77648656155840 is a wasteful number, since it uses less digits than its factorization.

77648656155840 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 391 (or 340 counting only the distinct ones).

The product of its (nonzero) digits is 1354752000, while the sum is 72.

The spelling of 77648656155840 in words is "seventy-seven trillion, six hundred forty-eight billion, six hundred fifty-six million, one hundred fifty-five thousand, eight hundred forty".