90597821 has 2 divisors, whose sum is σ = 90597822. Its totient is φ = 90597820.

The previous prime is 90597799. The next prime is 90597853. The reversal of 90597821 is 12879509.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 61058596 + 29539225 = 7814^2 + 5435^2 .

It is a cyclic number.

It is not a de Polignac number, because 90597821 - 2¹⁴ = 90581437 is a prime.

It is a Chen prime.

It is a plaindrome in base 16.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (90591821) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 45298910 + 45298911.

It is an arithmetic number, because the mean of its divisors is an integer number (45298911).

Almost surely, 2^90597821 is an apocalyptic number.

It is an amenable number.

90597821 is a deficient number, since it is larger than the sum of its proper divisors (1).

90597821 is an equidigital number, since it uses as much as digits as its factorization.

90597821 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 45360, while the sum is 41.

The square root of 90597821 is about 9518.2887642685. The cubic root of 90597821 is about 449.1305367948.

The spelling of 90597821 in words is "ninety million, five hundred ninety-seven thousand, eight hundred twenty-one".