20561059 has 4 divisors (see below), whose sum is σ = 21643240. Its totient is φ = 19478880.

The previous prime is 20561053. The next prime is 20561069. The reversal of 20561059 is 95016502.

20561059 = 717² + 718² + ... + 754².

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 20561059 - 2¹⁷ = 20429987 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20561053) 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, 541062 + ... + 541099.

It is an arithmetic number, because the mean of its divisors is an integer number (5410810).

Almost surely, 2^20561059 is an apocalyptic number.

20561059 is a deficient number, since it is larger than the sum of its proper divisors (1082181).

20561059 is a wasteful number, since it uses less digits than its factorization.

20561059 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1082180.

The product of its (nonzero) digits is 2700, while the sum is 28.

The square root of 20561059 is about 4534.4303942171. The cubic root of 20561059 is about 273.9566370719.

The spelling of 20561059 in words is "twenty million, five hundred sixty-one thousand, fifty-nine".