21523283 has 2 divisors, whose sum is σ = 21523284. Its totient is φ = 21523282.

The previous prime is 21523277. The next prime is 21523339. The reversal of 21523283 is 38232512.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21523283 - 2⁴ = 21523267 is a prime.

It is a super-2 number, since 2×21523283² = 926503422196178, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (21523273) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10761641 + 10761642.

It is an arithmetic number, because the mean of its divisors is an integer number (10761642).

Almost surely, 2^21523283 is an apocalyptic number.

21523283 is a deficient number, since it is larger than the sum of its proper divisors (1).

21523283 is an equidigital number, since it uses as much as digits as its factorization.

21523283 is an evil number, because the sum of its binary digits is even.

The product of its digits is 2880, while the sum is 26.

The square root of 21523283 is about 4639.3192388539. The cubic root of 21523283 is about 278.1652270729.

Adding to 21523283 its reverse (38232512), we get a palindrome (59755795).

The spelling of 21523283 in words is "twenty-one million, five hundred twenty-three thousand, two hundred eighty-three".