79777440 has 192 divisors, whose sum is σ = 284860800. Its totient is φ = 20846592.

The previous prime is 79777387. The next prime is 79777441. The reversal of 79777440 is 4477797.

It is a Smith number, since the sum of its digits (45) coincides with the sum of the digits of its prime factors.

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

It is not an unprimeable number, because it can be changed into a prime (79777441) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 254724 + ... + 255036.

It is an arithmetic number, because the mean of its divisors is an integer number (1483650).

Almost surely, 2^79777440 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 79777440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (142430400).

79777440 is an abundant number, since it is smaller than the sum of its proper divisors (205083360).

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

79777440 is a wasteful number, since it uses less digits than its factorization.

79777440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 396 (or 382 counting only the distinct ones).

The product of its (nonzero) digits is 345744, while the sum is 45.

The square root of 79777440 is about 8931.8217626641. The cubic root of 79777440 is about 430.4869910721.

The spelling of 79777440 in words is "seventy-nine million, seven hundred seventy-seven thousand, four hundred forty".