20900055 has 32 divisors (see below), whose sum is σ = 38631168. Its totient is φ = 9536000.

The previous prime is 20900053. The next prime is 20900059. The reversal of 20900055 is 55000902.

It is not a de Polignac number, because 20900055 - 2¹ = 20900053 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20900051) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 921 + ... + 6530.

It is an arithmetic number, because the mean of its divisors is an integer number (1207224).

Almost surely, 2^20900055 is an apocalyptic number.

20900055 is a deficient number, since it is larger than the sum of its proper divisors (17731113).

20900055 is a wasteful number, since it uses less digits than its factorization.

20900055 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7487.

The product of its (nonzero) digits is 450, while the sum is 21.

The square root of 20900055 is about 4571.6577955923. The cubic root of 20900055 is about 275.4540378286.

Adding to 20900055 its reverse (55000902), we get a palindrome (75900957).

The spelling of 20900055 in words is "twenty million, nine hundred thousand, fifty-five".