79178643769 has 27 divisors (see below), whose sum is σ = 85005261549. Its totient is φ = 73745904960.

The previous prime is 79178643757. The next prime is 79178643793. The reversal of 79178643769 is 96734687197.

The square root of 79178643769 is 281387.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in 4 ways, for example, as 31387437225 + 47791206544 = 177165^2 + 218612^2 .

It is not a de Polignac number, because 79178643769 - 2¹¹ = 79178641721 is a prime.

It is a super-2 number, since 2×79178643769² (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 (79178643799) by changing a digit.

It is a polite number, since it can be written in 26 ways as a sum of consecutive naturals, for example, 252966757 + ... + 252967069.

Almost surely, 2^79178643769 is an apocalyptic number.

79178643769 is the 281387-th square number.

79178643769 is the 140694-th centered octagonal number.

It is an amenable number.

79178643769 is a deficient number, since it is larger than the sum of its proper divisors (5826617780).

79178643769 is an frugal number, since it uses more digits than its factorization.

79178643769 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 746 (or 373 counting only the distinct ones).

The product of its digits is 96018048, while the sum is 67.

The spelling of 79178643769 in words is "seventy-nine billion, one hundred seventy-eight million, six hundred forty-three thousand, seven hundred sixty-nine".