91587381 has 16 divisors (see below), whose sum is σ = 129527424. Its totient is φ = 57365504.

The previous prime is 91587371. The next prime is 91587421. The reversal of 91587381 is 18378519.

It is a cyclic number.

It is not a de Polignac number, because 91587381 - 2¹⁰ = 91586357 is a prime.

It is a super-2 number, since 2×91587381² = 16776496716878322, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (91587341) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 36685 + ... + 39101.

It is an arithmetic number, because the mean of its divisors is an integer number (8095464).

Almost surely, 2^91587381 is an apocalyptic number.

It is an amenable number.

91587381 is a deficient number, since it is larger than the sum of its proper divisors (37940043).

91587381 is a wasteful number, since it uses less digits than its factorization.

91587381 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3180.

The product of its digits is 60480, while the sum is 42.

The square root of 91587381 is about 9570.1296229466. The cubic root of 91587381 is about 450.7598372596.

The spelling of 91587381 in words is "ninety-one million, five hundred eighty-seven thousand, three hundred eighty-one".