90500061661 has 4 divisors (see below), whose sum is σ = 90501248032. Its totient is φ = 90498875292.

The previous prime is 90500061611. The next prime is 90500061689. The reversal of 90500061661 is 16616000509.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 90500061661 - 2⁹ = 90500061149 is a prime.

It is a super-2 number, since 2×90500061661² (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 (90500061611) 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 3 ways as a sum of consecutive naturals, for example, 470271 + ... + 634156.

It is an arithmetic number, because the mean of its divisors is an integer number (22625312008).

Almost surely, 2^90500061661 is an apocalyptic number.

It is an amenable number.

90500061661 is a deficient number, since it is larger than the sum of its proper divisors (1186371).

90500061661 is a wasteful number, since it uses less digits than its factorization.

90500061661 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1186370.

The product of its (nonzero) digits is 9720, while the sum is 34.

The spelling of 90500061661 in words is "ninety billion, five hundred million, sixty-one thousand, six hundred sixty-one".