21840583 has 2 divisors, whose sum is σ = 21840584. Its totient is φ = 21840582.

The previous prime is 21840551. The next prime is 21840607. The reversal of 21840583 is 38504812.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21840583 - 2⁵ = 21840551 is a prime.

It is a super-2 number, since 2×21840583² = 954022131559778, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21840083) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10920291 + 10920292.

It is an arithmetic number, because the mean of its divisors is an integer number (10920292).

Almost surely, 2^21840583 is an apocalyptic number.

21840583 is a deficient number, since it is larger than the sum of its proper divisors (1).

21840583 is an equidigital number, since it uses as much as digits as its factorization.

21840583 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 7680, while the sum is 31.

The square root of 21840583 is about 4673.3909530447. The cubic root of 21840583 is about 279.5254845592.

The spelling of 21840583 in words is "twenty-one million, eight hundred forty thousand, five hundred eighty-three".