21027536 has 20 divisors (see below), whose sum is σ = 40817700. Its totient is φ = 10493952.

The previous prime is 21027529. The next prime is 21027557. The reversal of 21027536 is 63572012.

It can be written as a sum of positive squares in 2 ways, for example, as 5973136 + 15054400 = 2444^2 + 3880^2 .

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 11450 + ... + 13158.

It is an arithmetic number, because the mean of its divisors is an integer number (2040885).

Almost surely, 2^21027536 is an apocalyptic number.

It is an amenable number.

21027536 is a deficient number, since it is larger than the sum of its proper divisors (19790164).

21027536 is a wasteful number, since it uses less digits than its factorization.

21027536 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2486 (or 2480 counting only the distinct ones).

The product of its (nonzero) digits is 2520, while the sum is 26.

The square root of 21027536 is about 4585.5791346350. The cubic root of 21027536 is about 276.0129518532.

Adding to 21027536 its reverse (63572012), we get a palindrome (84599548).

The spelling of 21027536 in words is "twenty-one million, twenty-seven thousand, five hundred thirty-six".