90208831831 has 4 divisors (see below), whose sum is σ = 90209854152. Its totient is φ = 90207809512.

The previous prime is 90208831793. The next prime is 90208831871. The reversal of 90208831831 is 13813880209.

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

It is a cyclic number.

It is not a de Polignac number, because 90208831831 - 2¹¹ = 90208829783 is a prime.

It is a super-2 number, since 2×90208831831² (a number of 23 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (90208831871) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 364840 + ... + 559933.

It is an arithmetic number, because the mean of its divisors is an integer number (22552463538).

Almost surely, 2^90208831831 is an apocalyptic number.

90208831831 is a deficient number, since it is larger than the sum of its proper divisors (1022321).

90208831831 is an equidigital number, since it uses as much as digits as its factorization.

90208831831 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1022320.

The product of its (nonzero) digits is 82944, while the sum is 43.

The spelling of 90208831831 in words is "ninety billion, two hundred eight million, eight hundred thirty-one thousand, eight hundred thirty-one".