55145491 has 2 divisors, whose sum is σ = 55145492. Its totient is φ = 55145490.

The previous prime is 55145473. The next prime is 55145507. The reversal of 55145491 is 19454155.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-55145491 is a prime.

It is not a weakly prime, because it can be changed into another prime (55145401) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 27572745 + 27572746.

It is an arithmetic number, because the mean of its divisors is an integer number (27572746).

Almost surely, 2^55145491 is an apocalyptic number.

55145491 is a deficient number, since it is larger than the sum of its proper divisors (1).

55145491 is an equidigital number, since it uses as much as digits as its factorization.

55145491 is an evil number, because the sum of its binary digits is even.

The product of its digits is 18000, while the sum is 34.

The square root of 55145491 is about 7426.0010099649. The cubic root of 55145491 is about 380.6302813467.

The spelling of 55145491 in words is "fifty-five million, one hundred forty-five thousand, four hundred ninety-one".