90445691 has 4 divisors (see below), whose sum is σ = 103366512. Its totient is φ = 77524872.

The previous prime is 90445687. The next prime is 90445703. The reversal of 90445691 is 19654409.

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 90445691 - 2² = 90445687 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (90445891) 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, 6460400 + ... + 6460413.

It is an arithmetic number, because the mean of its divisors is an integer number (25841628).

Almost surely, 2^90445691 is an apocalyptic number.

90445691 is a deficient number, since it is larger than the sum of its proper divisors (12920821).

90445691 is a wasteful number, since it uses less digits than its factorization.

90445691 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12920820.

The product of its (nonzero) digits is 38880, while the sum is 38.

The square root of 90445691 is about 9510.2939491900. The cubic root of 90445691 is about 448.8790056964.

The spelling of 90445691 in words is "ninety million, four hundred forty-five thousand, six hundred ninety-one".