21022465 has 4 divisors (see below), whose sum is σ = 25226964. Its totient is φ = 16817968.

The previous prime is 21022459. The next prime is 21022471. The reversal of 21022465 is 56422012.

It is a semiprime because it is the product of two primes.

It is an interprime number because it is at equal distance from previous prime (21022459) and next prime (21022471).

It can be written as a sum of positive squares in 2 ways, for example, as 7997584 + 13024881 = 2828^2 + 3609^2 .

It is a cyclic number.

It is not a de Polignac number, because 21022465 - 2⁹ = 21021953 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2102242 + ... + 2102251.

It is an arithmetic number, because the mean of its divisors is an integer number (6306741).

Almost surely, 2^21022465 is an apocalyptic number.

It is an amenable number.

21022465 is a deficient number, since it is larger than the sum of its proper divisors (4204499).

21022465 is an equidigital number, since it uses as much as digits as its factorization.

21022465 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4204498.

The product of its (nonzero) digits is 960, while the sum is 22.

The square root of 21022465 is about 4585.0261722263. The cubic root of 21022465 is about 275.9907623107.

Adding to 21022465 its reverse (56422012), we get a palindrome (77444477).

The spelling of 21022465 in words is "twenty-one million, twenty-two thousand, four hundred sixty-five".