20623913 has 4 divisors (see below), whose sum is σ = 20700288. Its totient is φ = 20547540.

The previous prime is 20623909. The next prime is 20623919. The reversal of 20623913 is 31932602.

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 not a de Polignac number, because 20623913 - 2² = 20623909 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20623919) 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, 37781 + ... + 38322.

It is an arithmetic number, because the mean of its divisors is an integer number (5175072).

Almost surely, 2^20623913 is an apocalyptic number.

It is an amenable number.

20623913 is a deficient number, since it is larger than the sum of its proper divisors (76375).

20623913 is an equidigital number, since it uses as much as digits as its factorization.

20623913 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 76374.

The product of its (nonzero) digits is 1944, while the sum is 26.

The square root of 20623913 is about 4541.3558548081. The cubic root of 20623913 is about 274.2355097716.

The spelling of 20623913 in words is "twenty million, six hundred twenty-three thousand, nine hundred thirteen".