79404421 has 2 divisors, whose sum is σ = 79404422. Its totient is φ = 79404420.

The previous prime is 79404419. The next prime is 79404449. The reversal of 79404421 is 12440497.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 65788321 + 13616100 = 8111^2 + 3690^2 .

It is a cyclic number.

It is not a de Polignac number, because 79404421 - 2¹ = 79404419 is a prime.

Together with 79404419, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (79405421) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 39702210 + 39702211.

It is an arithmetic number, because the mean of its divisors is an integer number (39702211).

Almost surely, 2^79404421 is an apocalyptic number.

It is an amenable number.

79404421 is a deficient number, since it is larger than the sum of its proper divisors (1).

79404421 is an equidigital number, since it uses as much as digits as its factorization.

79404421 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 8064, while the sum is 31.

The square root of 79404421 is about 8910.9158339645. The cubic root of 79404421 is about 429.8149934252.

The spelling of 79404421 in words is "seventy-nine million, four hundred four thousand, four hundred twenty-one".