2521643 has 2 divisors, whose sum is σ = 2521644. Its totient is φ = 2521642.

The previous prime is 2521621. The next prime is 2521681. The reversal of 2521643 is 3461252.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 2521643 - 2¹⁴ = 2505259 is a prime.

It is not a weakly prime, because it can be changed into another prime (2521613) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1260821 + 1260822.

It is an arithmetic number, because the mean of its divisors is an integer number (1260822).

2^2521643 is an apocalyptic number.

2521643 is a deficient number, since it is larger than the sum of its proper divisors (1).

2521643 is an equidigital number, since it uses as much as digits as its factorization.

2521643 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1440, while the sum is 23.

The square root of 2521643 is about 1587.9681986740. The cubic root of 2521643 is about 136.1114102944. Note that the first 3 decimals are identical.

Adding to 2521643 its reverse (3461252), we get a palindrome (5982895).

The spelling of 2521643 in words is "two million, five hundred twenty-one thousand, six hundred forty-three".