2547721 has 4 divisors (see below), whose sum is σ = 2779344. Its totient is φ = 2316100.

The previous prime is 2547719. The next prime is 2547757. The reversal of 2547721 is 1277452.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 2547721 - 2¹ = 2547719 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 2547721.

It is not an unprimeable number, because it can be changed into a prime (2547761) 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, 115795 + ... + 115816.

It is an arithmetic number, because the mean of its divisors is an integer number (694836).

2^2547721 is an apocalyptic number.

It is an amenable number.

2547721 is a deficient number, since it is larger than the sum of its proper divisors (231623).

2547721 is a wasteful number, since it uses less digits than its factorization.

2547721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 231622.

The product of its digits is 3920, while the sum is 28.

The square root of 2547721 is about 1596.1582001794. The cubic root of 2547721 is about 136.5790084981.

The spelling of 2547721 in words is "two million, five hundred forty-seven thousand, seven hundred twenty-one".