77956645 has 16 divisors (see below), whose sum is σ = 106671600. Its totient is φ = 54180864.

The previous prime is 77956631. The next prime is 77956649. The reversal of 77956645 is 54665977.

It can be written as a sum of positive squares in 8 ways, for example, as 3272481 + 74684164 = 1809^2 + 8642^2 .

It is a cyclic number.

It is not a de Polignac number, because 77956645 - 2⁷ = 77956517 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (77956649) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 34170 + ... + 36379.

It is an arithmetic number, because the mean of its divisors is an integer number (6666975).

Almost surely, 2^77956645 is an apocalyptic number.

It is an amenable number.

77956645 is a deficient number, since it is larger than the sum of its proper divisors (28714955).

77956645 is a wasteful number, since it uses less digits than its factorization.

77956645 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 70584.

The product of its digits is 1587600, while the sum is 49.

The square root of 77956645 is about 8829.3060316199. The cubic root of 77956645 is about 427.1866906276.

The spelling of 77956645 in words is "seventy-seven million, nine hundred fifty-six thousand, six hundred forty-five".