20478365 has 4 divisors (see below), whose sum is σ = 24574044. Its totient is φ = 16382688.

The previous prime is 20478329. The next prime is 20478373. The reversal of 20478365 is 56387402.

It is a happy number.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 6205081 + 14273284 = 2491^2 + 3778^2 .

It is a cyclic number.

It is not a de Polignac number, because 20478365 - 2⁸ = 20478109 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2047832 + ... + 2047841.

It is an arithmetic number, because the mean of its divisors is an integer number (6143511).

Almost surely, 2^20478365 is an apocalyptic number.

It is an amenable number.

20478365 is a deficient number, since it is larger than the sum of its proper divisors (4095679).

20478365 is an equidigital number, since it uses as much as digits as its factorization.

20478365 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4095678.

The product of its (nonzero) digits is 40320, while the sum is 35.

The square root of 20478365 is about 4525.3027523029. The cubic root of 20478365 is about 273.5888705176.

The spelling of 20478365 in words is "twenty million, four hundred seventy-eight thousand, three hundred sixty-five".