2723721 has 32 divisors (see below), whose sum is σ = 4881408. Its totient is φ = 1304640.

The previous prime is 2723719. The next prime is 2723731. The reversal of 2723721 is 1273272.

2723721 = 126² + 127² + ... + 216².

2723721 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 2723721 - 2¹ = 2723719 is a prime.

It is a Curzon number.

2723721 is a lucky number.

It is a junction number, because it is equal to n+sod(n) for n = 2723691 and 2723700.

It is not an unprimeable number, because it can be changed into a prime (2723701) 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 31 ways as a sum of consecutive naturals, for example, 2550 + ... + 3456.

It is an arithmetic number, because the mean of its divisors is an integer number (152544).

2^2723721 is an apocalyptic number.

2723721 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

It is an amenable number.

2723721 is a deficient number, since it is larger than the sum of its proper divisors (2157687).

2723721 is a wasteful number, since it uses less digits than its factorization.

2723721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 941.

The product of its digits is 1176, while the sum is 24.

The square root of 2723721 is about 1650.3699585245. The cubic root of 2723721 is about 139.6542659502.

Adding to 2723721 its reverse (1273272), we get a palindrome (3996993).

It can be divided in two parts, 272 and 3721, that added together give a palindrome (3993).

The spelling of 2723721 in words is "two million, seven hundred twenty-three thousand, seven hundred twenty-one".