21523822 has 16 divisors (see below), whose sum is σ = 33176880. Its totient is φ = 10467072.

The previous prime is 21523813. The next prime is 21523847. The reversal of 21523822 is 22832512.

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, 30004 + ... + 30712.

It is an arithmetic number, because the mean of its divisors is an integer number (2073555).

Almost surely, 2^21523822 is an apocalyptic number.

21523822 is a deficient number, since it is larger than the sum of its proper divisors (11653058).

21523822 is a wasteful number, since it uses less digits than its factorization.

21523822 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1107.

The product of its digits is 1920, while the sum is 25.

The square root of 21523822 is about 4639.3773289096. The cubic root of 21523822 is about 278.1675490515.

The spelling of 21523822 in words is "twenty-one million, five hundred twenty-three thousand, eight hundred twenty-two".