21852136 has 8 divisors (see below), whose sum is σ = 40972770. Its totient is φ = 10926064.

The previous prime is 21852121. The next prime is 21852137. The reversal of 21852136 is 63125812.

It can be written as a sum of positive squares in only one way, i.e., 12888100 + 8964036 = 3590^2 + 2994^2 .

It is a tau number, because it is divible by the number of its divisors (8).

It is a hoax number, since the sum of its digits (28) coincides with the sum of the digits of its distinct prime factors.

It is not an unprimeable number, because it can be changed into a prime (21852137) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1365751 + ... + 1365766.

Almost surely, 2^21852136 is an apocalyptic number.

It is an amenable number.

21852136 is a deficient number, since it is larger than the sum of its proper divisors (19120634).

21852136 is a wasteful number, since it uses less digits than its factorization.

21852136 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2731523 (or 2731519 counting only the distinct ones).

The product of its digits is 2880, while the sum is 28.

The square root of 21852136 is about 4674.6268300261. The cubic root of 21852136 is about 279.5747626803.

Adding to 21852136 its reverse (63125812), we get a palindrome (84977948).

The spelling of 21852136 in words is "twenty-one million, eight hundred fifty-two thousand, one hundred thirty-six".