387221 has 4 divisors (see below), whose sum is σ = 399744. Its totient is φ = 374700.

The previous prime is 387203. The next prime is 387227. The reversal of 387221 is 122783.

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, and also an emirpimes, since its reverse is a distinct semiprime: 122783 = 199 ⋅617.

It is a cyclic number.

It is not a de Polignac number, because 387221 - 2¹⁴ = 370837 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 387221.

It is not an unprimeable number, because it can be changed into a prime (387227) 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, 6215 + ... + 6276.

It is an arithmetic number, because the mean of its divisors is an integer number (99936).

2³⁸⁷²²¹ is an apocalyptic number.

387221 is a gapful number since it is divisible by the number (31) formed by its first and last digit.

It is an amenable number.

387221 is a deficient number, since it is larger than the sum of its proper divisors (12523).

387221 is a wasteful number, since it uses less digits than its factorization.

387221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12522.

The product of its digits is 672, while the sum is 23.

The square root of 387221 is about 622.2708413545. The cubic root of 387221 is about 72.8874853935.

The spelling of 387221 in words is "three hundred eighty-seven thousand, two hundred twenty-one".