90851601601 has 4 divisors (see below), whose sum is σ = 90934420932. Its totient is φ = 90768782272.

The previous prime is 90851601593. The next prime is 90851601619. The reversal of 90851601601 is 10610615809.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 10610615809 = 14723 ⋅720683.

It can be written as a sum of positive squares in 2 ways, for example, as 55375502400 + 35476099201 = 235320^2 + 188351^2 .

It is a cyclic number.

It is not a de Polignac number, because 90851601601 - 2³ = 90851601593 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (90851601661) 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, 41408020 + ... + 41410213.

It is an arithmetic number, because the mean of its divisors is an integer number (22733605233).

Almost surely, 2^90851601601 is an apocalyptic number.

It is an amenable number.

90851601601 is a deficient number, since it is larger than the sum of its proper divisors (82819331).

90851601601 is a wasteful number, since it uses less digits than its factorization.

90851601601 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 82819330.

The product of its (nonzero) digits is 12960, while the sum is 37.

The spelling of 90851601601 in words is "ninety billion, eight hundred fifty-one million, six hundred one thousand, six hundred one".