21135650 has 24 divisors (see below), whose sum is σ = 39590100. Its totient is φ = 8394560.

The previous prime is 21135649. The next prime is 21135677. The reversal of 21135650 is 5653112.

It can be written as a sum of positive squares in 6 ways, for example, as 332929 + 20802721 = 577^2 + 4561^2 .

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 6032 + ... + 8868.

Almost surely, 2^21135650 is an apocalyptic number.

21135650 is a deficient number, since it is larger than the sum of its proper divisors (18454450).

21135650 is a wasteful number, since it uses less digits than its factorization.

21135650 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2998 (or 2993 counting only the distinct ones).

The product of its (nonzero) digits is 900, while the sum is 23.

The square root of 21135650 is about 4597.3524989933. The cubic root of 21135650 is about 276.4851876738.

Adding to 21135650 its reverse (5653112), we get a palindrome (26788762).

The spelling of 21135650 in words is "twenty-one million, one hundred thirty-five thousand, six hundred fifty".