21973065 has 16 divisors (see below), whose sum is σ = 35313408. Its totient is φ = 11666816.

The previous prime is 21973051. The next prime is 21973069. The reversal of 21973065 is 56037912.

It is a cyclic number.

It is not a de Polignac number, because 21973065 - 2⁵ = 21973033 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21973069) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 352 + ... + 6638.

It is an arithmetic number, because the mean of its divisors is an integer number (2207088).

Almost surely, 2^21973065 is an apocalyptic number.

It is an amenable number.

21973065 is a deficient number, since it is larger than the sum of its proper divisors (13340343).

21973065 is a wasteful number, since it uses less digits than its factorization.

21973065 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6528.

The product of its (nonzero) digits is 11340, while the sum is 33.

The square root of 21973065 is about 4687.5435997972. The cubic root of 21973065 is about 280.0895334424.

The spelling of 21973065 in words is "twenty-one million, nine hundred seventy-three thousand, sixty-five".