21836744 has 8 divisors (see below), whose sum is σ = 40943910. Its totient is φ = 10918368.

The previous prime is 21836701. The next prime is 21836767. The reversal of 21836744 is 44763812.

It can be written as a sum of positive squares in only one way, i.e., 12460900 + 9375844 = 3530^2 + 3062^2 .

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

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1364789 + ... + 1364804.

Almost surely, 2^21836744 is an apocalyptic number.

It is an amenable number.

21836744 is a deficient number, since it is larger than the sum of its proper divisors (19107166).

21836744 is a wasteful number, since it uses less digits than its factorization.

21836744 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2729599 (or 2729595 counting only the distinct ones).

The product of its digits is 32256, while the sum is 35.

The square root of 21836744 is about 4672.9802053936. The cubic root of 21836744 is about 279.5091058570.

The spelling of 21836744 in words is "twenty-one million, eight hundred thirty-six thousand, seven hundred forty-four".