21852820090 has 12 divisors (see below), whose sum is σ = 39335917626. Its totient is φ = 8740941048.

The previous prime is 21852820081. The next prime is 21852820127. The reversal of 21852820090 is 9002825812.

It can be written as a sum of positive squares in only one way, i.e., 19667538081 + 2185282009 = 140241^2 + 46747^2 .

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 444097 + ... + 490843.

Almost surely, 2^21852820090 is an apocalyptic number.

21852820090 is a deficient number, since it is larger than the sum of its proper divisors (17483097536).

21852820090 is an frugal number, since it uses more digits than its factorization.

21852820090 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 93501 (or 46754 counting only the distinct ones).

The product of its (nonzero) digits is 23040, while the sum is 37.

Multiplying 21852820090 by its product of nonzero digits (23040), we get a square (503488974873600 = 22438560²).

The spelling of 21852820090 in words is "twenty-one billion, eight hundred fifty-two million, eight hundred twenty thousand, ninety".