20164405 has 4 divisors (see below), whose sum is σ = 24197292. Its totient is φ = 16131520.

The previous prime is 20164393. The next prime is 20164409. The reversal of 20164405 is 50446102.

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 4498641 + 15665764 = 2121^2 + 3958^2 .

It is not a de Polignac number, because 20164405 - 2⁵ = 20164373 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 (20164409) 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, 2016436 + ... + 2016445.

It is an arithmetic number, because the mean of its divisors is an integer number (6049323).

Almost surely, 2^20164405 is an apocalyptic number.

It is an amenable number.

20164405 is a deficient number, since it is larger than the sum of its proper divisors (4032887).

20164405 is an equidigital number, since it uses as much as digits as its factorization.

20164405 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4032886.

The product of its (nonzero) digits is 960, while the sum is 22.

The square root of 20164405 is about 4490.4793730737. The cubic root of 20164405 is about 272.1835059629.

The spelling of 20164405 in words is "twenty million, one hundred sixty-four thousand, four hundred five".