77307444 has 18 divisors (see below), whose sum is σ = 195416130. Its totient is φ = 25769136.

The previous prime is 77307437. The next prime is 77307469. The reversal of 77307444 is 44470377.

It can be written as a sum of positive squares in only one way, i.e., 72897444 + 4410000 = 8538^2 + 2100^2 .

It is a tau number, because it is divible by the number of its divisors (18).

It is a Harshad number since it is a multiple of its sum of digits (36), and also a Moran number because the ratio is a prime number: 2147429 = 77307444 / (7 + 7 + 3 + 0 + 7 + 4 + 4 + 4).

It is a junction number, because it is equal to n+sod(n) for n = 77307399 and 77307408.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 1073679 + ... + 1073750.

Almost surely, 2^77307444 is an apocalyptic number.

It is an amenable number.

77307444 is an abundant number, since it is smaller than the sum of its proper divisors (118108686).

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

77307444 is a wasteful number, since it uses less digits than its factorization.

77307444 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2147439 (or 2147434 counting only the distinct ones).

The product of its (nonzero) digits is 65856, while the sum is 36.

The square root of 77307444 is about 8792.4651833260. The cubic root of 77307444 is about 425.9975533814.

The spelling of 77307444 in words is "seventy-seven million, three hundred seven thousand, four hundred forty-four".