20553859 has 4 divisors (see below), whose sum is σ = 20677104. Its totient is φ = 20430616.

The previous prime is 20553853. The next prime is 20553887. The reversal of 20553859 is 95835502.

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

It is a cyclic number.

It is not a de Polignac number, because 20553859 - 2²¹ = 18456707 is a prime.

It is a super-2 number, since 2×20553859² = 844922239583762, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20553853) 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, 61372 + ... + 61705.

It is an arithmetic number, because the mean of its divisors is an integer number (5169276).

Almost surely, 2^20553859 is an apocalyptic number.

20553859 is a deficient number, since it is larger than the sum of its proper divisors (123245).

20553859 is a wasteful number, since it uses less digits than its factorization.

20553859 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 123244.

The product of its (nonzero) digits is 54000, while the sum is 37.

The square root of 20553859 is about 4533.6363991833. The cubic root of 20553859 is about 273.9246556117.

It can be divided in two parts, 20553 and 859, that added together give a palindrome (21412).

The spelling of 20553859 in words is "twenty million, five hundred fifty-three thousand, eight hundred fifty-nine".