77745645 has 24 divisors (see below), whose sum is σ = 135000216. Its totient is φ = 41390208.

The previous prime is 77745643. The next prime is 77745653. The reversal of 77745645 is 54654777.

It can be written as a sum of positive squares in 4 ways, for example, as 15824484 + 61921161 = 3978^2 + 7869^2 .

It is not a de Polignac number, because 77745645 - 2¹ = 77745643 is a prime.

It is a super-3 number, since 3×77745645³ (a number of 25 digits) contains 333 as substring.

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

It is a self number, because there is not a number n which added to its sum of digits gives 77745645.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (77745643) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 31807 + ... + 34163.

It is an arithmetic number, because the mean of its divisors is an integer number (5625009).

Almost surely, 2^77745645 is an apocalyptic number.

It is an amenable number.

77745645 is a deficient number, since it is larger than the sum of its proper divisors (57254571).

77745645 is a wasteful number, since it uses less digits than its factorization.

77745645 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3101 (or 3098 counting only the distinct ones).

The product of its digits is 823200, while the sum is 45.

The square root of 77745645 is about 8817.3490914220. The cubic root of 77745645 is about 426.8009299001.

The spelling of 77745645 in words is "seventy-seven million, seven hundred forty-five thousand, six hundred forty-five".