2991221 has 8 divisors (see below), whose sum is σ = 3154944. Its totient is φ = 2831760.

The previous prime is 2991217. The next prime is 2991229. The reversal of 2991221 is 1221992.

It is a happy number.

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

It is a cyclic number.

It is not a de Polignac number, because 2991221 - 2² = 2991217 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2991229) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 431 + ... + 2483.

It is an arithmetic number, because the mean of its divisors is an integer number (394368).

2^2991221 is an apocalyptic number.

It is an amenable number.

2991221 is a deficient number, since it is larger than the sum of its proper divisors (163723).

2991221 is a wasteful number, since it uses less digits than its factorization.

2991221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2131.

The product of its digits is 648, while the sum is 26.

The square root of 2991221 is about 1729.5146718083. The cubic root of 2991221 is about 144.0841361452.

The spelling of 2991221 in words is "two million, nine hundred ninety-one thousand, two hundred twenty-one".