79965421 has 4 divisors (see below), whose sum is σ = 80174592. Its totient is φ = 79756252.

The previous prime is 79965407. The next prime is 79965439. The reversal of 79965421 is 12456997.

It is a happy number.

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: 12456997 = 7 ⋅1779571.

It is a cyclic number.

It is not a de Polignac number, because 79965421 - 2⁹ = 79964909 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (79965451) 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 3 ways as a sum of consecutive naturals, for example, 104011 + ... + 104776.

It is an arithmetic number, because the mean of its divisors is an integer number (20043648).

Almost surely, 2^79965421 is an apocalyptic number.

It is an amenable number.

79965421 is a deficient number, since it is larger than the sum of its proper divisors (209171).

79965421 is a wasteful number, since it uses less digits than its factorization.

79965421 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 209170.

The product of its digits is 136080, while the sum is 43.

The square root of 79965421 is about 8942.3386762077. The cubic root of 79965421 is about 430.8248472286.

The spelling of 79965421 in words is "seventy-nine million, nine hundred sixty-five thousand, four hundred twenty-one".