55904909 has 2 divisors, whose sum is σ = 55904910. Its totient is φ = 55904908.

The previous prime is 55904887. The next prime is 55904911. The reversal of 55904909 is 90940955.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 52852900 + 3052009 = 7270^2 + 1747^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-55904909 is a prime.

Together with 55904911, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (55904939) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 27952454 + 27952455.

It is an arithmetic number, because the mean of its divisors is an integer number (27952455).

Almost surely, 2^55904909 is an apocalyptic number.

It is an amenable number.

55904909 is a deficient number, since it is larger than the sum of its proper divisors (1).

55904909 is an equidigital number, since it uses as much as digits as its factorization.

55904909 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 72900, while the sum is 41.

The square root of 55904909 is about 7476.9585394062. The cubic root of 55904909 is about 382.3695632254.

The spelling of 55904909 in words is "fifty-five million, nine hundred four thousand, nine hundred nine".