55157909 has 2 divisors, whose sum is σ = 55157910. Its totient is φ = 55157908.

The previous prime is 55157903. The next prime is 55157917. The reversal of 55157909 is 90975155.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 27857284 + 27300625 = 5278^2 + 5225^2 .

It is a cyclic number.

It is not a de Polignac number, because 55157909 - 2²⁰ = 54109333 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (55157903) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 27578954 + 27578955.

It is an arithmetic number, because the mean of its divisors is an integer number (27578955).

Almost surely, 2^55157909 is an apocalyptic number.

It is an amenable number.

55157909 is a deficient number, since it is larger than the sum of its proper divisors (1).

55157909 is an equidigital number, since it uses as much as digits as its factorization.

55157909 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 70875, while the sum is 41.

The square root of 55157909 is about 7426.8370791340. The cubic root of 55157909 is about 380.6588500898.

The spelling of 55157909 in words is "fifty-five million, one hundred fifty-seven thousand, nine hundred nine".