21660674 has 8 divisors (see below), whose sum is σ = 37132608. Its totient is φ = 9283140.

The previous prime is 21660643. The next prime is 21660677. The reversal of 21660674 is 47606612.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a self number, because there is not a number n which added to its sum of digits gives 21660674.

It is not an unprimeable number, because it can be changed into a prime (21660677) by changing a digit.

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 3 ways as a sum of consecutive naturals, for example, 773582 + ... + 773609.

It is an arithmetic number, because the mean of its divisors is an integer number (4641576).

Almost surely, 2^21660674 is an apocalyptic number.

21660674 is a deficient number, since it is larger than the sum of its proper divisors (15471934).

21660674 is a wasteful number, since it uses less digits than its factorization.

21660674 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1547200.

The product of its (nonzero) digits is 12096, while the sum is 32.

The square root of 21660674 is about 4654.1029210794. The cubic root of 21660674 is about 278.7558489794.

The spelling of 21660674 in words is "twenty-one million, six hundred sixty thousand, six hundred seventy-four".