79780910977440 has 336 divisors, whose sum is σ = 282662715141576. Its totient is φ = 21269761228800.

The previous prime is 79780910977421. The next prime is 79780910977441. The reversal of 79780910977440 is 4477901908797.

It is a happy number.

79780910977440 is a `hidden beast` number, since 7 + 9 + 7 + 8 + 0 + 9 + 109 + 77 + 440 = 666.

It can be written as a sum of positive squares in 4 ways, for example, as 76491606418704 + 3289304558736 = 8745948^2 + 1813644^2 .

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

It is not an unprimeable number, because it can be changed into a prime (79780910977441) by changing a digit.

It is a polite number, since it can be written in 55 ways as a sum of consecutive naturals, for example, 494589600 + ... + 494750880.

Almost surely, 2^{79780910977440} 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 79780910977440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (141331357570788).

79780910977440 is an abundant number, since it is smaller than the sum of its proper divisors (202881804164136).

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

79780910977440 is a wasteful number, since it uses less digits than its factorization.

79780910977440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 165555 (or 165532 counting only the distinct ones).

The product of its (nonzero) digits is 224042112, while the sum is 72.

The spelling of 79780910977440 in words is "seventy-nine trillion, seven hundred eighty billion, nine hundred ten million, nine hundred seventy-seven thousand, four hundred forty".