90506221746891 has 16 divisors (see below), whose sum is σ = 120750906511488. Its totient is φ = 60299510169600.

The previous prime is 90506221746827. The next prime is 90506221746907. The reversal of 90506221746891 is 19864712260509.

90506221746891 is digitally balanced in base 4, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 90506221746891 - 2⁶ = 90506221746827 is a prime.

It is not an unprimeable number, because it can be changed into a prime (90506221746791) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 649693956 + ... + 649833246.

It is an arithmetic number, because the mean of its divisors is an integer number (7546931656968).

Almost surely, 2^{90506221746891} is an apocalyptic number.

90506221746891 is a deficient number, since it is larger than the sum of its proper divisors (30244684764597).

90506221746891 is a wasteful number, since it uses less digits than its factorization.

90506221746891 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 274042.

The product of its (nonzero) digits is 13063680, while the sum is 60.

The spelling of 90506221746891 in words is "ninety trillion, five hundred six billion, two hundred twenty-one million, seven hundred forty-six thousand, eight hundred ninety-one".