2540921 has 4 divisors (see below), whose sum is σ = 2550372. Its totient is φ = 2531472.

The previous prime is 2540903. The next prime is 2540933. The reversal of 2540921 is 1290452.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 215296 + 2325625 = 464^2 + 1525^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-2540921 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (2540981) 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, 4310 + ... + 4863.

It is an arithmetic number, because the mean of its divisors is an integer number (637593).

2^2540921 is an apocalyptic number.

It is an amenable number.

2540921 is a deficient number, since it is larger than the sum of its proper divisors (9451).

2540921 is an equidigital number, since it uses as much as digits as its factorization.

2540921 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9450.

The product of its (nonzero) digits is 720, while the sum is 23.

The square root of 2540921 is about 1594.0266622613. The cubic root of 2540921 is about 136.4573880685.

The spelling of 2540921 in words is "two million, five hundred forty thousand, nine hundred twenty-one".