7977912169 has 4 divisors (see below), whose sum is σ = 7989458320. Its totient is φ = 7966366020.

The previous prime is 7977912157. The next prime is 7977912191. The reversal of 7977912169 is 9612197797.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 9612197797 = 10369 ⋅927013.

It is a cyclic number.

It is not a de Polignac number, because 7977912169 - 2¹⁵ = 7977879401 is a prime.

It is a super-2 number, since 2×7977912169² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (7977912119) 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, 5772039 + ... + 5773420.

It is an arithmetic number, because the mean of its divisors is an integer number (1997364580).

Almost surely, 2^7977912169 is an apocalyptic number.

It is an amenable number.

7977912169 is a deficient number, since it is larger than the sum of its proper divisors (11546151).

7977912169 is a wasteful number, since it uses less digits than its factorization.

7977912169 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11546150.

The product of its digits is 3000564, while the sum is 58.

The square root of 7977912169 is about 89319.1590253737. The cubic root of 7977912169 is about 1998.1576508125.

The spelling of 7977912169 in words is "seven billion, nine hundred seventy-seven million, nine hundred twelve thousand, one hundred sixty-nine".