2221751 has 8 divisors (see below), whose sum is σ = 2548224. Its totient is φ = 1897560.

The previous prime is 2221741. The next prime is 2221753. The reversal of 2221751 is 1571222.

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

It is a de Polignac number, because none of the positive numbers 2^k-2221751 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2221753) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3206 + ... + 3836.

It is an arithmetic number, because the mean of its divisors is an integer number (318528).

2^2221751 is an apocalyptic number.

2221751 is a deficient number, since it is larger than the sum of its proper divisors (326473).

2221751 is an equidigital number, since it uses as much as digits as its factorization.

2221751 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1141.

The product of its digits is 280, while the sum is 20.

The square root of 2221751 is about 1490.5539238820. The cubic root of 2221751 is about 130.4863635238.

Adding to 2221751 its reverse (1571222), we get a palindrome (3792973).

The spelling of 2221751 in words is "two million, two hundred twenty-one thousand, seven hundred fifty-one".