55546991 has 2 divisors, whose sum is σ = 55546992. Its totient is φ = 55546990.

The previous prime is 55546969. The next prime is 55546999. The reversal of 55546991 is 19964555.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 55546991 - 2¹⁰ = 55545967 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (55546999) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 27773495 + 27773496.

It is an arithmetic number, because the mean of its divisors is an integer number (27773496).

Almost surely, 2^55546991 is an apocalyptic number.

55546991 is a deficient number, since it is larger than the sum of its proper divisors (1).

55546991 is an equidigital number, since it uses as much as digits as its factorization.

55546991 is an evil number, because the sum of its binary digits is even.

The product of its digits is 243000, while the sum is 44.

The square root of 55546991 is about 7452.9853750024. The cubic root of 55546991 is about 381.5518052393.

The spelling of 55546991 in words is "fifty-five million, five hundred forty-six thousand, nine hundred ninety-one".