21852036 has 18 divisors (see below), whose sum is σ = 55237182. Its totient is φ = 7284000.

The previous prime is 21852029. The next prime is 21852037. The reversal of 21852036 is 63025812.

It can be written as a sum of positive squares in only one way, i.e., 17690436 + 4161600 = 4206^2 + 2040^2 .

It is a tau number, because it is divible by the number of its divisors (18).

It is a super-2 number, since 2×21852036² = 955022954690592, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (21852037) by changing a digit.

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 5 ways as a sum of consecutive naturals, for example, 303465 + ... + 303536.

Almost surely, 2^21852036 is an apocalyptic number.

It is an amenable number.

21852036 is an abundant number, since it is smaller than the sum of its proper divisors (33385146).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21852036 is a wasteful number, since it uses less digits than its factorization.

21852036 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 607011 (or 607006 counting only the distinct ones).

The product of its (nonzero) digits is 2880, while the sum is 27.

The square root of 21852036 is about 4674.6161339729. The cubic root of 21852036 is about 279.5743362152.

Adding to 21852036 its reverse (63025812), we get a palindrome (84877848).

The spelling of 21852036 in words is "twenty-one million, eight hundred fifty-two thousand, thirty-six".