77815402889380 has 48 divisors (see below), whose sum is σ = 176954805793584. Its totient is φ = 28573101596160.

The previous prime is 77815402889369. The next prime is 77815402889381. The reversal of 77815402889380 is 8398820451877.

It is a happy number.

It can be written as a sum of positive squares in 8 ways, for example, as 34742748912804 + 43072653976576 = 5894298^2 + 6562976^2 .

It is a Smith number, since the sum of its digits (70) coincides with the sum of the digits of its prime factors.

It is not an unprimeable number, because it can be changed into a prime (77815402889381) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 826720927 + ... + 826815046.

It is an arithmetic number, because the mean of its divisors is an integer number (3686558454033).

Almost surely, 2^{77815402889380} is an apocalyptic number.

It is an amenable number.

77815402889380 is an abundant number, since it is smaller than the sum of its proper divisors (99139402904204).

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

77815402889380 is a wasteful number, since it uses less digits than its factorization.

77815402889380 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1653536176 (or 1653536174 counting only the distinct ones).

The product of its (nonzero) digits is 216760320, while the sum is 70.

The spelling of 77815402889380 in words is "seventy-seven trillion, eight hundred fifteen billion, four hundred two million, eight hundred eighty-nine thousand, three hundred eighty".