90581391 has 12 divisors (see below), whose sum is σ = 131840280. Its totient is φ = 59925840.

The previous prime is 90581377. The next prime is 90581437. The reversal of 90581391 is 19318509.

It is a happy number.

It is not a de Polignac number, because 90581391 - 2¹¹ = 90579343 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (90581311) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 37236 + ... + 39593.

It is an arithmetic number, because the mean of its divisors is an integer number (10986690).

Almost surely, 2^90581391 is an apocalyptic number.

90581391 is a deficient number, since it is larger than the sum of its proper divisors (41258889).

90581391 is a wasteful number, since it uses less digits than its factorization.

90581391 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 76966 (or 76963 counting only the distinct ones).

The product of its (nonzero) digits is 9720, while the sum is 36.

The square root of 90581391 is about 9517.4256498278. The cubic root of 90581391 is about 449.1033850717.

The spelling of 90581391 in words is "ninety million, five hundred eighty-one thousand, three hundred ninety-one".