20145623 has 4 divisors (see below), whose sum is σ = 20154648. Its totient is φ = 20136600.

The previous prime is 20145617. The next prime is 20145673. The reversal of 20145623 is 32654102.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is not a de Polignac number, because 20145623 - 2⁴ = 20145607 is a prime.

It is a super-2 number, since 2×20145623² = 811692252116258, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20145613) 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, 1565 + ... + 6537.

It is an arithmetic number, because the mean of its divisors is an integer number (5038662).

Almost surely, 2^20145623 is an apocalyptic number.

20145623 is a deficient number, since it is larger than the sum of its proper divisors (9025).

20145623 is an equidigital number, since it uses as much as digits as its factorization.

20145623 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9024.

The product of its (nonzero) digits is 1440, while the sum is 23.

The square root of 20145623 is about 4488.3875723917. The cubic root of 20145623 is about 272.0989718766.

Adding to 20145623 its reverse (32654102), we get a palindrome (52799725).

The spelling of 20145623 in words is "twenty million, one hundred forty-five thousand, six hundred twenty-three".