856893221 has 4 divisors (see below), whose sum is σ = 894149472. Its totient is φ = 819636972.

The previous prime is 856893209. The next prime is 856893229. The reversal of 856893221 is 122398658.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 856893221 - 2¹⁴ = 856876837 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (856893229) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 18628091 + ... + 18628136.

It is an arithmetic number, because the mean of its divisors is an integer number (223537368).

Almost surely, 2^856893221 is an apocalyptic number.

It is an amenable number.

856893221 is a deficient number, since it is larger than the sum of its proper divisors (37256251).

856893221 is a wasteful number, since it uses less digits than its factorization.

856893221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 37256250.

The product of its digits is 207360, while the sum is 44.

The square root of 856893221 is about 29272.7385292186. The cubic root of 856893221 is about 949.8220242773.

The spelling of 856893221 in words is "eight hundred fifty-six million, eight hundred ninety-three thousand, two hundred twenty-one".