77461577744 has 20 divisors (see below), whose sum is σ = 151409967996. Its totient is φ = 38388037632.

The previous prime is 77461577671. The next prime is 77461577747. The reversal of 77461577744 is 44777516477.

It can be written as a sum of positive squares in 2 ways, for example, as 38059327744 + 39402250000 = 195088^2 + 198500^2 .

It is a super-2 number, since 2×77461577744² (a number of 23 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (77461577747) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 21420089 + ... + 21423704.

Almost surely, 2^77461577744 is an apocalyptic number.

It is an amenable number.

77461577744 is a deficient number, since it is larger than the sum of its proper divisors (73948390252).

77461577744 is a wasteful number, since it uses less digits than its factorization.

77461577744 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 42843914 (or 42843908 counting only the distinct ones).

The product of its digits is 32269440, while the sum is 59.

The spelling of 77461577744 in words is "seventy-seven billion, four hundred sixty-one million, five hundred seventy-seven thousand, seven hundred forty-four".