2521403 has 4 divisors (see below), whose sum is σ = 2534400. Its totient is φ = 2508408.

The previous prime is 2521397. The next prime is 2521417. The reversal of 2521403 is 3041252.

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

It is a cyclic number.

It is not a de Polignac number, because 2521403 - 2⁶ = 2521339 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (2521003) 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 3 ways as a sum of consecutive naturals, for example, 6203 + ... + 6596.

It is an arithmetic number, because the mean of its divisors is an integer number (633600).

2^2521403 is an apocalyptic number.

2521403 is a deficient number, since it is larger than the sum of its proper divisors (12997).

2521403 is a wasteful number, since it uses less digits than its factorization.

2521403 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12996.

The product of its (nonzero) digits is 240, while the sum is 17.

The square root of 2521403 is about 1587.8926286119. The cubic root of 2521403 is about 136.1070919757.

Adding to 2521403 its reverse (3041252), we get a palindrome (5562655).

The spelling of 2521403 in words is "two million, five hundred twenty-one thousand, four hundred three".