77666767440 has 40 divisors (see below), whose sum is σ = 240766979808. Its totient is φ = 20711137920.

The previous prime is 77666767427. The next prime is 77666767447. The reversal of 77666767440 is 4476766677.

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

It is a Harshad number since it is a multiple of its sum of digits (60).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (77666767447) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 161805526 + ... + 161806005.

Almost surely, 2^77666767440 is an apocalyptic number.

It is an amenable number.

77666767440 is an abundant number, since it is smaller than the sum of its proper divisors (163100212368).

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

77666767440 is a wasteful number, since it uses less digits than its factorization.

77666767440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 323611547 (or 323611541 counting only the distinct ones).

The product of its (nonzero) digits is 49787136, while the sum is 60.

The spelling of 77666767440 in words is "seventy-seven billion, six hundred sixty-six million, seven hundred sixty-seven thousand, four hundred forty".