20559149 has 4 divisors (see below), whose sum is σ = 22140636. Its totient is φ = 18977664.

The previous prime is 20559127. The next prime is 20559157. The reversal of 20559149 is 94195502.

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 1357225 + 19201924 = 1165^2 + 4382^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20559149 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 (20559449) 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, 790724 + ... + 790749.

It is an arithmetic number, because the mean of its divisors is an integer number (5535159).

Almost surely, 2^20559149 is an apocalyptic number.

It is an amenable number.

20559149 is a deficient number, since it is larger than the sum of its proper divisors (1581487).

20559149 is a wasteful number, since it uses less digits than its factorization.

20559149 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1581486.

The product of its (nonzero) digits is 16200, while the sum is 35.

The square root of 20559149 is about 4534.2197785286. The cubic root of 20559149 is about 273.9481538289.

The spelling of 20559149 in words is "twenty million, five hundred fifty-nine thousand, one hundred forty-nine".