21065122 has 16 divisors (see below), whose sum is σ = 34345080. Its totient is φ = 9631872.

The previous prime is 21065117. The next prime is 21065123. The reversal of 21065122 is 22156012.

It can be written as a sum of positive squares in 4 ways, for example, as 11148921 + 9916201 = 3339^2 + 3149^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 21065122.

It is not an unprimeable number, because it can be changed into a prime (21065123) 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 7 ways as a sum of consecutive naturals, for example, 883 + ... + 6550.

Almost surely, 2^21065122 is an apocalyptic number.

21065122 is a deficient number, since it is larger than the sum of its proper divisors (13279958).

21065122 is a wasteful number, since it uses less digits than its factorization.

21065122 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7557.

The product of its (nonzero) digits is 240, while the sum is 19.

The square root of 21065122 is about 4589.6755876641. The cubic root of 21065122 is about 276.1773085289.

The spelling of 21065122 in words is "twenty-one million, sixty-five thousand, one hundred twenty-two".