21853365 has 8 divisors (see below), whose sum is σ = 34965408. Its totient is φ = 11655120.

The previous prime is 21853343. The next prime is 21853373. The reversal of 21853365 is 56335812.

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

It is not a de Polignac number, because 21853365 - 2¹⁴ = 21836981 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 728431 + ... + 728460.

It is an arithmetic number, because the mean of its divisors is an integer number (4370676).

Almost surely, 2^21853365 is an apocalyptic number.

It is an amenable number.

21853365 is a deficient number, since it is larger than the sum of its proper divisors (13112043).

21853365 is a wasteful number, since it uses less digits than its factorization.

21853365 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1456899.

The product of its digits is 21600, while the sum is 33.

The square root of 21853365 is about 4674.7582825211. The cubic root of 21853365 is about 279.5800038299.

The spelling of 21853365 in words is "twenty-one million, eight hundred fifty-three thousand, three hundred sixty-five".