91240281 has 24 divisors (see below), whose sum is σ = 147122976. Its totient is φ = 54008640.

The previous prime is 91240277. The next prime is 91240307. The reversal of 91240281 is 18204219.

It is not a de Polignac number, because 91240281 - 2² = 91240277 is a prime.

It is a super-2 number, since 2×91240281² = 16649577753917922, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (91240231) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 6460 + ... + 14973.

It is an arithmetic number, because the mean of its divisors is an integer number (6130124).

Almost surely, 2^91240281 is an apocalyptic number.

It is an amenable number.

91240281 is a deficient number, since it is larger than the sum of its proper divisors (55882695).

91240281 is a wasteful number, since it uses less digits than its factorization.

91240281 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 21493 (or 21490 counting only the distinct ones).

The product of its (nonzero) digits is 1152, while the sum is 27.

The square root of 91240281 is about 9551.9778580145. The cubic root of 91240281 is about 450.1896829970.

The spelling of 91240281 in words is "ninety-one million, two hundred forty thousand, two hundred eighty-one".