20415479 has 4 divisors (see below), whose sum is σ = 23331984. Its totient is φ = 17498976.

The previous prime is 20415469. The next prime is 20415491. The reversal of 20415479 is 97451402.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 97451402 = 2 ⋅48725701.

It is a cyclic number.

It is not a de Polignac number, because 20415479 - 2⁴ = 20415463 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 (20415469) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1458242 + ... + 1458255.

It is an arithmetic number, because the mean of its divisors is an integer number (5832996).

Almost surely, 2^20415479 is an apocalyptic number.

20415479 is a deficient number, since it is larger than the sum of its proper divisors (2916505).

20415479 is an equidigital number, since it uses as much as digits as its factorization.

20415479 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2916504.

The product of its (nonzero) digits is 10080, while the sum is 32.

The square root of 20415479 is about 4518.3491454291. The cubic root of 20415479 is about 273.3085331785.

The spelling of 20415479 in words is "twenty million, four hundred fifteen thousand, four hundred seventy-nine".