91625551 has 2 divisors, whose sum is σ = 91625552. Its totient is φ = 91625550.

The previous prime is 91625539. The next prime is 91625557. The reversal of 91625551 is 15552619.

It is a strong prime.

It is an emirp because it is prime and its reverse (15552619) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 91625551 - 2⁵ = 91625519 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (91625557) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 45812775 + 45812776.

It is an arithmetic number, because the mean of its divisors is an integer number (45812776).

Almost surely, 2^91625551 is an apocalyptic number.

91625551 is a deficient number, since it is larger than the sum of its proper divisors (1).

91625551 is an equidigital number, since it uses as much as digits as its factorization.

91625551 is an evil number, because the sum of its binary digits is even.

The product of its digits is 13500, while the sum is 34.

The square root of 91625551 is about 9572.1236410736. The cubic root of 91625551 is about 450.8224481898.

The spelling of 91625551 in words is "ninety-one million, six hundred twenty-five thousand, five hundred fifty-one".