77428523681 has 16 divisors (see below), whose sum is σ = 79002000000. Its totient is φ = 75864233856.

The previous prime is 77428523671. The next prime is 77428523693. The reversal of 77428523681 is 18632582477.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-77428523681 is a prime.

It is a super-2 number, since 2×77428523681² (a number of 23 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (77428523671) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 28164695 + ... + 28167443.

It is an arithmetic number, because the mean of its divisors is an integer number (4937625000).

Almost surely, 2^77428523681 is an apocalyptic number.

It is an amenable number.

77428523681 is a deficient number, since it is larger than the sum of its proper divisors (1573476319).

77428523681 is a wasteful number, since it uses less digits than its factorization.

77428523681 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4216.

The product of its digits is 4515840, while the sum is 53.

The spelling of 77428523681 in words is "seventy-seven billion, four hundred twenty-eight million, five hundred twenty-three thousand, six hundred eighty-one".