79666019 has 4 divisors (see below), whose sum is σ = 79846296. Its totient is φ = 79485744.

The previous prime is 79666009. The next prime is 79666021. The reversal of 79666019 is 91066697.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 79666019 - 2¹⁶ = 79600483 is a prime.

It is a super-2 number, since 2×79666019² = 12693349166616722, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (79666009) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 89474 + ... + 90359.

It is an arithmetic number, because the mean of its divisors is an integer number (19961574).

Almost surely, 2^79666019 is an apocalyptic number.

79666019 is a deficient number, since it is larger than the sum of its proper divisors (180277).

79666019 is a wasteful number, since it uses less digits than its factorization.

79666019 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 180276.

The product of its (nonzero) digits is 122472, while the sum is 44.

The square root of 79666019 is about 8925.5822779245. The cubic root of 79666019 is about 430.2864847695.

The spelling of 79666019 in words is "seventy-nine million, six hundred sixty-six thousand, nineteen".