20457079 has 4 divisors (see below), whose sum is σ = 20892384. Its totient is φ = 20021776.

The previous prime is 20457067. The next prime is 20457119. The reversal of 20457079 is 97075402.

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 20457079 - 2⁷ = 20456951 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 (20457029) 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, 217582 + ... + 217675.

It is an arithmetic number, because the mean of its divisors is an integer number (5223096).

Almost surely, 2^20457079 is an apocalyptic number.

20457079 is a deficient number, since it is larger than the sum of its proper divisors (435305).

20457079 is an equidigital number, since it uses as much as digits as its factorization.

20457079 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 435304.

The product of its (nonzero) digits is 17640, while the sum is 34.

The square root of 20457079 is about 4522.9502539825. The cubic root of 20457079 is about 273.4940447241.

The spelling of 20457079 in words is "twenty million, four hundred fifty-seven thousand, seventy-nine".