21586937 has 2 divisors, whose sum is σ = 21586938. Its totient is φ = 21586936.

The previous prime is 21586927. The next prime is 21586963. The reversal of 21586937 is 73968512.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 17172736 + 4414201 = 4144^2 + 2101^2 .

It is a cyclic number.

It is not a de Polignac number, because 21586937 - 2¹⁰ = 21585913 is a prime.

It is a Chen prime.

It is a junction number, because it is equal to n+sod(n) for n = 21586894 and 21586903.

It is not a weakly prime, because it can be changed into another prime (21586927) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10793468 + 10793469.

It is an arithmetic number, because the mean of its divisors is an integer number (10793469).

Almost surely, 2^21586937 is an apocalyptic number.

It is an amenable number.

21586937 is a deficient number, since it is larger than the sum of its proper divisors (1).

21586937 is an equidigital number, since it uses as much as digits as its factorization.

21586937 is an evil number, because the sum of its binary digits is even.

The product of its digits is 90720, while the sum is 41.

The square root of 21586937 is about 4646.1744478657. The cubic root of 21586937 is about 278.4391769593.

The spelling of 21586937 in words is "twenty-one million, five hundred eighty-six thousand, nine hundred thirty-seven".