91487555 has 4 divisors (see below), whose sum is σ = 109785072. Its totient is φ = 73190040.

The previous prime is 91487551. The next prime is 91487573. The reversal of 91487555 is 55578419.

It is a semiprime because it is the product of two primes.

It is not a de Polignac number, because 91487555 - 2² = 91487551 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (91487551) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 9148751 + ... + 9148760.

It is an arithmetic number, because the mean of its divisors is an integer number (27446268).

Almost surely, 2^91487555 is an apocalyptic number.

91487555 is a deficient number, since it is larger than the sum of its proper divisors (18297517).

91487555 is a wasteful number, since it uses less digits than its factorization.

91487555 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 18297516.

The product of its digits is 252000, while the sum is 44.

The square root of 91487555 is about 9564.9127021630. The cubic root of 91487555 is about 450.5960086137.

The spelling of 91487555 in words is "ninety-one million, four hundred eighty-seven thousand, five hundred fifty-five".