91412987 has 4 divisors (see below), whose sum is σ = 91792536. Its totient is φ = 91033440.

The previous prime is 91412983. The next prime is 91413011. The reversal of 91412987 is 78921419.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 78921419 = 1213 ⋅65063.

It is a cyclic number.

It is not a de Polignac number, because 91412987 - 2² = 91412983 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (91412983) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 189413 + ... + 189894.

It is an arithmetic number, because the mean of its divisors is an integer number (22948134).

Almost surely, 2^91412987 is an apocalyptic number.

91412987 is a deficient number, since it is larger than the sum of its proper divisors (379549).

91412987 is a wasteful number, since it uses less digits than its factorization.

91412987 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 379548.

The product of its digits is 36288, while the sum is 41.

The square root of 91412987 is about 9561.0139106687. The cubic root of 91412987 is about 450.4735541589.

The spelling of 91412987 in words is "ninety-one million, four hundred twelve thousand, nine hundred eighty-seven".