77257578640 has 40 divisors (see below), whose sum is σ = 195953315328. Its totient is φ = 28093664640.

The previous prime is 77257578589. The next prime is 77257578641. The reversal of 77257578640 is 4687575277.

It is a tau number, because it is divible by the number of its divisors (40).

It is a Smith number, since the sum of its digits (58) coincides with the sum of the digits of its prime factors.

It is not an unprimeable number, because it can be changed into a prime (77257578641) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 43895472 + ... + 43897231.

Almost surely, 2^77257578640 is an apocalyptic number.

It is an amenable number.

77257578640 is an abundant number, since it is smaller than the sum of its proper divisors (118695736688).

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

77257578640 is a wasteful number, since it uses less digits than its factorization.

77257578640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 87792727 (or 87792721 counting only the distinct ones).

The product of its (nonzero) digits is 23049600, while the sum is 58.

The spelling of 77257578640 in words is "seventy-seven billion, two hundred fifty-seven million, five hundred seventy-eight thousand, six hundred forty".