20821522 has 16 divisors (see below), whose sum is σ = 33030144. Its totient is φ = 9828000.

The previous prime is 20821519. The next prime is 20821547. The reversal of 20821522 is 22512802.

It is a junction number, because it is equal to n+sod(n) for n = 20821493 and 20821502.

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, 1554 + ... + 6637.

It is an arithmetic number, because the mean of its divisors is an integer number (2064384).

Almost surely, 2^20821522 is an apocalyptic number.

20821522 is a deficient number, since it is larger than the sum of its proper divisors (12208622).

20821522 is a wasteful number, since it uses less digits than its factorization.

20821522 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8265.

The product of its (nonzero) digits is 640, while the sum is 22.

The square root of 20821522 is about 4563.0605956967. The cubic root of 20821522 is about 275.1085940265.

The spelling of 20821522 in words is "twenty million, eight hundred twenty-one thousand, five hundred twenty-two".