2639221 has 4 divisors (see below), whose sum is σ = 2842252. Its totient is φ = 2436192.

The previous prime is 2639213. The next prime is 2639239. The reversal of 2639221 is 1229362.

It is a happy number.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 202500 + 2436721 = 450^2 + 1561^2 .

It is a cyclic number.

It is not a de Polignac number, because 2639221 - 2³ = 2639213 is a prime.

It is a d-powerful number, because it can be written as 2⁵ + 6³ + 3⁷ + 9⁶ + 2¹³ + 2²¹ + 1 .

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2639201) 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, 101496 + ... + 101521.

It is an arithmetic number, because the mean of its divisors is an integer number (710563).

2^2639221 is an apocalyptic number.

It is an amenable number.

2639221 is a deficient number, since it is larger than the sum of its proper divisors (203031).

2639221 is a wasteful number, since it uses less digits than its factorization.

2639221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 203030.

The product of its digits is 1296, while the sum is 25.

The square root of 2639221 is about 1624.5679425620. The cubic root of 2639221 is about 138.1948692738.

The spelling of 2639221 in words is "two million, six hundred thirty-nine thousand, two hundred twenty-one".