21849656 has 8 divisors (see below), whose sum is σ = 40968120. Its totient is φ = 10924824.

The previous prime is 21849643. The next prime is 21849671. The reversal of 21849656 is 65694812.

It is a happy number.

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

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1365596 + ... + 1365611.

It is an arithmetic number, because the mean of its divisors is an integer number (5121015).

Almost surely, 2^21849656 is an apocalyptic number.

It is an amenable number.

21849656 is a deficient number, since it is larger than the sum of its proper divisors (19118464).

21849656 is a wasteful number, since it uses less digits than its factorization.

21849656 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2731213 (or 2731209 counting only the distinct ones).

The product of its digits is 103680, while the sum is 41.

The square root of 21849656 is about 4674.3615606840. The cubic root of 21849656 is about 279.5641859622.

The spelling of 21849656 in words is "twenty-one million, eight hundred forty-nine thousand, six hundred fifty-six".