77440000 has 165 divisors, whose sum is σ = 212628031. Its totient is φ = 28160000.

The previous prime is 77439997. The next prime is 77440043. The reversal of 77440000 is 4477.

It is a happy number.

The square root of 77440000 is 8800.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in 2 ways, for example, as 6071296 + 71368704 = 2464^2 + 8448^2 .

It is a Harshad number since it is a multiple of its sum of digits (22).

It is a nialpdrome in base 10.

It is a zygodrome in base 10.

It is an unprimeable number.

It is a polite number, since it can be written in 14 ways as a sum of consecutive naturals, for example, 7039995 + ... + 7040005.

Almost surely, 2^77440000 is an apocalyptic number.

77440000 is the 8800-th square number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 77440000

77440000 is an abundant number, since it is smaller than the sum of its proper divisors (135188031).

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

77440000 is an equidigital number, since it uses as much as digits as its factorization.

77440000 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 62 (or 18 counting only the distinct ones).

The product of its (nonzero) digits is 784, while the sum is 22.

The cubic root of 77440000 is about 426.2408947066.

Multiplying 77440000 by its product of nonzero digits (784), we get a square (60712960000 = 246400²).

Adding to 77440000 its reverse (4477), we get a palindrome (77444477).

The spelling of 77440000 in words is "seventy-seven million, four hundred forty thousand".