2351721 has 8 divisors (see below), whose sum is σ = 3142720. Its totient is φ = 1564272.

The previous prime is 2351693. The next prime is 2351731. The reversal of 2351721 is 1271532.

2351721 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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

It is not a de Polignac number, because 2351721 - 2¹⁰ = 2350697 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a plaindrome in base 6.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2351731) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2100 + ... + 3018.

It is an arithmetic number, because the mean of its divisors is an integer number (392840).

2^2351721 is an apocalyptic number.

It is an amenable number.

2351721 is a deficient number, since it is larger than the sum of its proper divisors (790999).

2351721 is an equidigital number, since it uses as much as digits as its factorization.

2351721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1775.

The product of its digits is 420, while the sum is 21.

The square root of 2351721 is about 1533.5321972492. The cubic root of 2351721 is about 132.9827365612.

The spelling of 2351721 in words is "two million, three hundred fifty-one thousand, seven hundred twenty-one".