79905149 has 4 divisors (see below), whose sum is σ = 79925664. Its totient is φ = 79884636.

The previous prime is 79905131. The next prime is 79905173. The reversal of 79905149 is 94150997.

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: 94150997 = 193 ⋅487829.

It is a cyclic number.

It is not a de Polignac number, because 79905149 - 2⁸ = 79904893 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 (79905949) 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, 2417 + ... + 12870.

It is an arithmetic number, because the mean of its divisors is an integer number (19981416).

Almost surely, 2^79905149 is an apocalyptic number.

It is an amenable number.

79905149 is a deficient number, since it is larger than the sum of its proper divisors (20515).

79905149 is a wasteful number, since it uses less digits than its factorization.

79905149 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 20514.

The product of its (nonzero) digits is 102060, while the sum is 44.

The square root of 79905149 is about 8938.9680053125. The cubic root of 79905149 is about 430.7165787565.

The spelling of 79905149 in words is "seventy-nine million, nine hundred five thousand, one hundred forty-nine".