20557853 has 2 divisors, whose sum is σ = 20557854. Its totient is φ = 20557852.

The previous prime is 20557819. The next prime is 20557861. The reversal of 20557853 is 35875502.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 18164644 + 2393209 = 4262^2 + 1547^2 .

It is a cyclic number.

It is not a de Polignac number, because 20557853 - 2⁸ = 20557597 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20557813) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10278926 + 10278927.

It is an arithmetic number, because the mean of its divisors is an integer number (10278927).

Almost surely, 2^20557853 is an apocalyptic number.

It is an amenable number.

20557853 is a deficient number, since it is larger than the sum of its proper divisors (1).

20557853 is an equidigital number, since it uses as much as digits as its factorization.

20557853 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 42000, while the sum is 35.

The square root of 20557853 is about 4534.0768630450. The cubic root of 20557853 is about 273.9423973606.

The spelling of 20557853 in words is "twenty million, five hundred fifty-seven thousand, eight hundred fifty-three".