91455551 has 12 divisors (see below), whose sum is σ = 101164056. Its totient is φ = 82613520.

The previous prime is 91455523. The next prime is 91455557. The reversal of 91455551 is 15555419.

It is a de Polignac number, because none of the positive numbers 2^k-91455551 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (91455557) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 17405 + ... + 22041.

It is an arithmetic number, because the mean of its divisors is an integer number (8430338).

Almost surely, 2^91455551 is an apocalyptic number.

91455551 is a deficient number, since it is larger than the sum of its proper divisors (9708505).

91455551 is a wasteful number, since it uses less digits than its factorization.

91455551 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4822 (or 4811 counting only the distinct ones).

The product of its digits is 22500, while the sum is 35.

The square root of 91455551 is about 9563.2395661721. The cubic root of 91455551 is about 450.5434602769.

It can be divided in two parts, 914 and 55551, that added together give a palindrome (56465).

The spelling of 91455551 in words is "ninety-one million, four hundred fifty-five thousand, five hundred fifty-one".