21465937 has 2 divisors, whose sum is σ = 21465938. Its totient is φ = 21465936.

The previous prime is 21465907. The next prime is 21465947. The reversal of 21465937 is 73956412.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 19395216 + 2070721 = 4404^2 + 1439^2 .

It is a cyclic number.

It is not a de Polignac number, because 21465937 - 2²³ = 13077329 is a prime.

It is a super-3 number, since 3×21465937³ (a number of 23 digits) contains 333 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 21465896 and 21465905.

It is not a weakly prime, because it can be changed into another prime (21465907) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10732968 + 10732969.

It is an arithmetic number, because the mean of its divisors is an integer number (10732969).

Almost surely, 2^21465937 is an apocalyptic number.

It is an amenable number.

21465937 is a deficient number, since it is larger than the sum of its proper divisors (1).

21465937 is an equidigital number, since it uses as much as digits as its factorization.

21465937 is an evil number, because the sum of its binary digits is even.

The product of its digits is 45360, while the sum is 37.

The square root of 21465937 is about 4633.1346839910. The cubic root of 21465937 is about 277.9179622672.

The spelling of 21465937 in words is "twenty-one million, four hundred sixty-five thousand, nine hundred thirty-seven".