21836634 has 16 divisors (see below), whose sum is σ = 44018688. Its totient is φ = 7221312.

The previous prime is 21836629. The next prime is 21836651. The reversal of 21836634 is 43663812.

It is a junction number, because it is equal to n+sod(n) for n = 21836595 and 21836604.

It is an unprimeable number.

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 7 ways as a sum of consecutive naturals, for example, 13567 + ... + 15090.

It is an arithmetic number, because the mean of its divisors is an integer number (2751168).

Almost surely, 2^21836634 is an apocalyptic number.

21836634 is an abundant number, since it is smaller than the sum of its proper divisors (22182054).

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

21836634 is a wasteful number, since it uses less digits than its factorization.

21836634 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 28789.

The product of its digits is 20736, while the sum is 33.

The square root of 21836634 is about 4672.9684355878. The cubic root of 21836634 is about 279.5086365249.

The spelling of 21836634 in words is "twenty-one million, eight hundred thirty-six thousand, six hundred thirty-four".