21536650 has 24 divisors (see below), whose sum is σ = 40181580. Its totient is φ = 8588160.

The previous prime is 21536629. The next prime is 21536657. The reversal of 21536650 is 5663512.

It can be written as a sum of positive squares in 6 ways, for example, as 5303809 + 16232841 = 2303^2 + 4029^2 .

It is not an unprimeable number, because it can be changed into a prime (21536657) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 28072 + ... + 28828.

Almost surely, 2^21536650 is an apocalyptic number.

21536650 is a deficient number, since it is larger than the sum of its proper divisors (18644930).

21536650 is a wasteful number, since it uses less digits than its factorization.

21536650 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1338 (or 1333 counting only the distinct ones).

The product of its (nonzero) digits is 5400, while the sum is 28.

The square root of 21536650 is about 4640.7596360941. The cubic root of 21536650 is about 278.2227998437. Note that the first 3 decimals are identical.

The spelling of 21536650 in words is "twenty-one million, five hundred thirty-six thousand, six hundred fifty".