77975629565 has 4 divisors (see below), whose sum is σ = 93570755484. Its totient is φ = 62380503648.

The previous prime is 77975629561. The next prime is 77975629607. The reversal of 77975629565 is 56592657977.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 56592657977 = 17 ⋅3328979881.

It can be written as a sum of positive squares in 2 ways, for example, as 8265900889 + 69709728676 = 90917^2 + 264026^2 .

It is a cyclic number.

It is not a de Polignac number, because 77975629565 - 2² = 77975629561 is a prime.

It is a super-4 number, since 4×77975629565⁴ (a number of 45 digits) contains 4444 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 77975629495 and 77975629504.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (77975629561) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 7797562952 + ... + 7797562961.

It is an arithmetic number, because the mean of its divisors is an integer number (23392688871).

Almost surely, 2^77975629565 is an apocalyptic number.

It is an amenable number.

77975629565 is a deficient number, since it is larger than the sum of its proper divisors (15595125919).

77975629565 is a wasteful number, since it uses less digits than its factorization.

77975629565 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15595125918.

The product of its digits is 250047000, while the sum is 68.

The spelling of 77975629565 in words is "seventy-seven billion, nine hundred seventy-five million, six hundred twenty-nine thousand, five hundred sixty-five".