21168851 has 8 divisors (see below), whose sum is σ = 23438784. Its totient is φ = 18956520.

The previous prime is 21168827. The next prime is 21168871. The reversal of 21168851 is 15886112.

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

It is not a de Polignac number, because 21168851 - 2²² = 16974547 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21168821) 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, 13625 + ... + 15098.

It is an arithmetic number, because the mean of its divisors is an integer number (2929848).

Almost surely, 2^21168851 is an apocalyptic number.

21168851 is a deficient number, since it is larger than the sum of its proper divisors (2269933).

21168851 is a wasteful number, since it uses less digits than its factorization.

21168851 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 28801.

The product of its digits is 3840, while the sum is 32.

The square root of 21168851 is about 4600.9619646330. The cubic root of 21168851 is about 276.6298844667.

The spelling of 21168851 in words is "twenty-one million, one hundred sixty-eight thousand, eight hundred fifty-one".