55327991 has 2 divisors, whose sum is σ = 55327992. Its totient is φ = 55327990.

The previous prime is 55327939. The next prime is 55327999. The reversal of 55327991 is 19972355.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 55327991 - 2¹⁰ = 55326967 is a prime.

It is a super-2 number, since 2×55327991² = 6122373176192162, which contains 22 as substring.

It is a Sophie Germain 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 (55327999) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 27663995 + 27663996.

It is an arithmetic number, because the mean of its divisors is an integer number (27663996).

Almost surely, 2^55327991 is an apocalyptic number.

55327991 is a deficient number, since it is larger than the sum of its proper divisors (1).

55327991 is an equidigital number, since it uses as much as digits as its factorization.

55327991 is an evil number, because the sum of its binary digits is even.

The product of its digits is 85050, while the sum is 41.

The square root of 55327991 is about 7438.2787659512. The cubic root of 55327991 is about 381.0497084286.

The spelling of 55327991 in words is "fifty-five million, three hundred twenty-seven thousand, nine hundred ninety-one".