21327851 has 8 divisors (see below), whose sum is σ = 21813360. Its totient is φ = 20846592.

The previous prime is 21327841. The next prime is 21327853. The reversal of 21327851 is 15872312.

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 21327851 - 2¹⁴ = 21311467 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21327853) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 10451 + ... + 12323.

It is an arithmetic number, because the mean of its divisors is an integer number (2726670).

Almost surely, 2^21327851 is an apocalyptic number.

21327851 is a deficient number, since it is larger than the sum of its proper divisors (485509).

21327851 is a wasteful number, since it uses less digits than its factorization.

21327851 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2125.

The product of its digits is 3360, while the sum is 29.

The square root of 21327851 is about 4618.2086353910. The cubic root of 21327851 is about 277.3207499697.

The spelling of 21327851 in words is "twenty-one million, three hundred twenty-seven thousand, eight hundred fifty-one".