21590201 has 2 divisors, whose sum is σ = 21590202. Its totient is φ = 21590200.

The previous prime is 21590183. The next prime is 21590237. The reversal of 21590201 is 10209512.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 14830201 + 6760000 = 3851^2 + 2600^2 .

It is a cyclic number.

It is not a de Polignac number, because 21590201 - 2¹⁸ = 21328057 is a prime.

It is a super-2 number, since 2×21590201² = 932273558440802, which contains 22 as substring.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (21590501) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10795100 + 10795101.

It is an arithmetic number, because the mean of its divisors is an integer number (10795101).

Almost surely, 2^21590201 is an apocalyptic number.

It is an amenable number.

21590201 is a deficient number, since it is larger than the sum of its proper divisors (1).

21590201 is an equidigital number, since it uses as much as digits as its factorization.

21590201 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 180, while the sum is 20.

The square root of 21590201 is about 4646.5256913096. The cubic root of 21590201 is about 278.4532098236.

Adding to 21590201 its reverse (10209512), we get a palindrome (31799713).

The spelling of 21590201 in words is "twenty-one million, five hundred ninety thousand, two hundred one".