2403521 has 2 divisors, whose sum is σ = 2403522. Its totient is φ = 2403520.

The previous prime is 2403517. The next prime is 2403547. The reversal of 2403521 is 1253042.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1290496 + 1113025 = 1136^2 + 1055^2 .

It is a cyclic number.

It is not a de Polignac number, because 2403521 - 2² = 2403517 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 2403521.

It is not a weakly prime, because it can be changed into another prime (2403551) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1201760 + 1201761.

It is an arithmetic number, because the mean of its divisors is an integer number (1201761).

2^2403521 is an apocalyptic number.

It is an amenable number.

2403521 is a deficient number, since it is larger than the sum of its proper divisors (1).

2403521 is an equidigital number, since it uses as much as digits as its factorization.

2403521 is an odious number, because the sum of its binary digits is odd.

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

The square root of 2403521 is about 1550.3293198543. The cubic root of 2403521 is about 133.9520322854.

Adding to 2403521 its reverse (1253042), we get a palindrome (3656563).

The spelling of 2403521 in words is "two million, four hundred three thousand, five hundred twenty-one".