77809213440 has 1344 divisors, whose sum is σ = 347896281600. Its totient is φ = 16116350976.

The previous prime is 77809213423. The next prime is 77809213441. The reversal of 77809213440 is 4431290877.

It is a tau number, because it is divible by the number of its divisors (1344).

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (77809213441) by changing a digit.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 3383009269 + ... + 3383009291.

It is an arithmetic number, because the mean of its divisors is an integer number (258851400).

Almost surely, 2^77809213440 is an apocalyptic number.

77809213440 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 77809213440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (173948140800).

77809213440 is an abundant number, since it is smaller than the sum of its proper divisors (270087068160).

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

77809213440 is a wasteful number, since it uses less digits than its factorization.

77809213440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 112 (or 59 counting only the distinct ones).

The product of its (nonzero) digits is 338688, while the sum is 45.

The spelling of 77809213440 in words is "seventy-seven billion, eight hundred nine million, two hundred thirteen thousand, four hundred forty".