77320144225 has 27 divisors (see below), whose sum is σ = 101223305427. Its totient is φ = 58580509680.

The previous prime is 77320144127. The next prime is 77320144241. The reversal of 77320144225 is 52244102377.

The square root of 77320144225 is 278065.

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

It can be written as a sum of positive squares in only one way, i.e., 27835251921 + 49484892304 = 166839^2 + 222452^2 .

It is not a de Polignac number, because 77320144225 - 2²¹ = 77318047073 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 26 ways as a sum of consecutive naturals, for example, 26414712 + ... + 26417638.

Almost surely, 2^77320144225 is an apocalyptic number.

77320144225 is the 278065-th square number.

77320144225 is the 139033-rd centered octagonal number.

It is an amenable number.

77320144225 is a deficient number, since it is larger than the sum of its proper divisors (23903161202).

77320144225 is an frugal number, since it uses more digits than its factorization.

77320144225 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5902 (or 2951 counting only the distinct ones).

The product of its (nonzero) digits is 94080, while the sum is 37.

The spelling of 77320144225 in words is "seventy-seven billion, three hundred twenty million, one hundred forty-four thousand, two hundred twenty-five".