77365077081721 has 32 divisors (see below), whose sum is σ = 91329320073600. Its totient is φ = 64608518177280.

The previous prime is 77365077081697. The next prime is 77365077081727. The reversal of 77365077081721 is 12718077056377.

It is not a de Polignac number, because 77365077081721 - 2¹¹ = 77365077079673 is a prime.

It is a Smith number, since the sum of its digits (61) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 77365077081721.

It is not an unprimeable number, because it can be changed into a prime (77365077081727) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 70813605 + ... + 71897821.

It is an arithmetic number, because the mean of its divisors is an integer number (2854041252300).

Almost surely, 2^{77365077081721} is an apocalyptic number.

It is an amenable number.

77365077081721 is a deficient number, since it is larger than the sum of its proper divisors (13964242991879).

77365077081721 is a wasteful number, since it uses less digits than its factorization.

77365077081721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1086649.

The product of its (nonzero) digits is 24202080, while the sum is 61.

The spelling of 77365077081721 in words is "seventy-seven trillion, three hundred sixty-five billion, seventy-seven million, eighty-one thousand, seven hundred twenty-one".