90541721 has 2 divisors, whose sum is σ = 90541722. Its totient is φ = 90541720.

The previous prime is 90541709. The next prime is 90541733. The reversal of 90541721 is 12714509.

It is a balanced prime because it is at equal distance from previous prime (90541709) and next prime (90541733).

It can be written as a sum of positive squares in only one way, i.e., 66912400 + 23629321 = 8180^2 + 4861^2 .

It is a cyclic number.

It is not a de Polignac number, because 90541721 - 2⁶ = 90541657 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is equal to p_5246660 and since 90541721 and 5246660 have the same sum of digits, it is a Honaker prime.

It is not a weakly prime, because it can be changed into another prime (90541771) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 45270860 + 45270861.

It is an arithmetic number, because the mean of its divisors is an integer number (45270861).

Almost surely, 2^90541721 is an apocalyptic number.

It is an amenable number.

90541721 is a deficient number, since it is larger than the sum of its proper divisors (1).

90541721 is an equidigital number, since it uses as much as digits as its factorization.

90541721 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2520, while the sum is 29.

The square root of 90541721 is about 9515.3413496311. The cubic root of 90541721 is about 449.0378140880.

The spelling of 90541721 in words is "ninety million, five hundred forty-one thousand, seven hundred twenty-one".