21015422 has 16 divisors (see below), whose sum is σ = 33315840. Its totient is φ = 9921912.

The previous prime is 21015419. The next prime is 21015437. The reversal of 21015422 is 22451012.

It is a self number, because there is not a number n which added to its sum of digits gives 21015422.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 743 + ... + 6525.

It is an arithmetic number, because the mean of its divisors is an integer number (2082240).

Almost surely, 2^21015422 is an apocalyptic number.

21015422 is a deficient number, since it is larger than the sum of its proper divisors (12300418).

21015422 is a wasteful number, since it uses less digits than its factorization.

21015422 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5887.

The product of its (nonzero) digits is 160, while the sum is 17.

The square root of 21015422 is about 4584.2580642891. The cubic root of 21015422 is about 275.9599378244.

Adding to 21015422 its reverse (22451012), we get a palindrome (43466434).

The spelling of 21015422 in words is "twenty-one million, fifteen thousand, four hundred twenty-two".