21149641 has 8 divisors (see below), whose sum is σ = 22317120. Its totient is φ = 19987632.

The previous prime is 21149629. The next prime is 21149659. The reversal of 21149641 is 14694112.

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

It is a cyclic number.

It is not a de Polignac number, because 21149641 - 2⁹ = 21149129 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21149041) by changing a digit.

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, 8451 + ... + 10663.

It is an arithmetic number, because the mean of its divisors is an integer number (2789640).

Almost surely, 2^21149641 is an apocalyptic number.

It is an amenable number.

21149641 is a deficient number, since it is larger than the sum of its proper divisors (1167479).

21149641 is a wasteful number, since it uses less digits than its factorization.

21149641 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2735.

The product of its digits is 1728, while the sum is 28.

The square root of 21149641 is about 4598.8738838981. The cubic root of 21149641 is about 276.5461817922.

The spelling of 21149641 in words is "twenty-one million, one hundred forty-nine thousand, six hundred forty-one".