20364509 has 4 divisors (see below), whose sum is σ = 22215840. Its totient is φ = 18513180.

The previous prime is 20364503. The next prime is 20364511. The reversal of 20364509 is 90546302.

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.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20364509 is a prime.

It is a super-2 number, since 2×20364509² = 829426453622162, which contains 22 as substring.

It is a Duffinian number.

It is a plaindrome in base 16.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20364503) 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, 925649 + ... + 925670.

It is an arithmetic number, because the mean of its divisors is an integer number (5553960).

Almost surely, 2^20364509 is an apocalyptic number.

It is an amenable number.

20364509 is a deficient number, since it is larger than the sum of its proper divisors (1851331).

20364509 is a wasteful number, since it uses less digits than its factorization.

20364509 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1851330.

The product of its (nonzero) digits is 6480, while the sum is 29.

The square root of 20364509 is about 4512.7052861892. The cubic root of 20364509 is about 273.0808930760.

The spelling of 20364509 in words is "twenty million, three hundred sixty-four thousand, five hundred nine".