91187963 has 4 divisors (see below), whose sum is σ = 91399968. Its totient is φ = 90975960.

The previous prime is 91187953. The next prime is 91187989. The reversal of 91187963 is 36978119.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 36978119 = 181 ⋅204299.

It is a cyclic number.

It is not a de Polignac number, because 91187963 - 2¹² = 91183867 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (91187923) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 105356 + ... + 106217.

It is an arithmetic number, because the mean of its divisors is an integer number (22849992).

Almost surely, 2^91187963 is an apocalyptic number.

91187963 is a deficient number, since it is larger than the sum of its proper divisors (212005).

91187963 is a wasteful number, since it uses less digits than its factorization.

91187963 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 212004.

The product of its digits is 81648, while the sum is 44.

The square root of 91187963 is about 9549.2388701927. The cubic root of 91187963 is about 450.1036189368.

The spelling of 91187963 in words is "ninety-one million, one hundred eighty-seven thousand, nine hundred sixty-three".