90251439661 has 8 divisors (see below), whose sum is σ = 94326072120. Its totient is φ = 86240974848.

The previous prime is 90251439647. The next prime is 90251439683. The reversal of 90251439661 is 16693415209.

It can be written as a sum of positive squares in 4 ways, for example, as 14306552100 + 75944887561 = 119610^2 + 275581^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 90251439661 - 2⁷ = 90251439533 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 (90251431661) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 16039036 + ... + 16044661.

It is an arithmetic number, because the mean of its divisors is an integer number (11790759015).

Almost surely, 2^90251439661 is an apocalyptic number.

It is an amenable number.

90251439661 is a deficient number, since it is larger than the sum of its proper divisors (4074632459).

90251439661 is a wasteful number, since it uses less digits than its factorization.

90251439661 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 32083823.

The product of its (nonzero) digits is 349920, while the sum is 46.

The spelling of 90251439661 in words is "ninety billion, two hundred fifty-one million, four hundred thirty-nine thousand, six hundred sixty-one".