90286991 has 4 divisors (see below), whose sum is σ = 90466992. Its totient is φ = 90106992.

The previous prime is 90286981. The next prime is 90287003. The reversal of 90286991 is 19968209.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-90286991 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (90286951) 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, 89246 + ... + 90251.

It is an arithmetic number, because the mean of its divisors is an integer number (22616748).

Almost surely, 2^90286991 is an apocalyptic number.

90286991 is a deficient number, since it is larger than the sum of its proper divisors (180001).

90286991 is a wasteful number, since it uses less digits than its factorization.

90286991 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 180000.

The product of its (nonzero) digits is 69984, while the sum is 44.

The square root of 90286991 is about 9501.9466952830. The cubic root of 90286991 is about 448.6163110217.

The spelling of 90286991 in words is "ninety million, two hundred eighty-six thousand, nine hundred ninety-one".