2857221 has 32 divisors (see below), whose sum is σ = 4561920. Its totient is φ = 1762992.

The previous prime is 2857219. The next prime is 2857223. The reversal of 2857221 is 1227582.

It is an interprime number because it is at equal distance from previous prime (2857219) and next prime (2857223).

It is not a de Polignac number, because 2857221 - 2¹ = 2857219 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2857223) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 26650 + ... + 26756.

It is an arithmetic number, because the mean of its divisors is an integer number (142560).

2^2857221 is an apocalyptic number.

It is an amenable number.

2857221 is a deficient number, since it is larger than the sum of its proper divisors (1704699).

2857221 is a wasteful number, since it uses less digits than its factorization.

2857221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 182 (or 176 counting only the distinct ones).

The product of its digits is 2240, while the sum is 27.

The square root of 2857221 is about 1690.3316242679. The cubic root of 2857221 is about 141.8996348251.

The spelling of 2857221 in words is "two million, eight hundred fifty-seven thousand, two hundred twenty-one".