2521261 has 4 divisors (see below), whose sum is σ = 2602624. Its totient is φ = 2439900.

The previous prime is 2521249. The next prime is 2521271. The reversal of 2521261 is 1621252.

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 a de Polignac number, because none of the positive numbers 2^k-2521261 is a prime.

It is a Duffinian number.

It is a plaindrome in base 16.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2521271) 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, 40635 + ... + 40696.

It is an arithmetic number, because the mean of its divisors is an integer number (650656).

2^2521261 is an apocalyptic number.

It is an amenable number.

2521261 is a deficient number, since it is larger than the sum of its proper divisors (81363).

2521261 is an equidigital number, since it uses as much as digits as its factorization.

2521261 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 81362.

The product of its digits is 240, while the sum is 19.

The square root of 2521261 is about 1587.8479146316. The cubic root of 2521261 is about 136.1045368414.

Subtracting from 2521261 its reverse (1621252), we obtain a palindrome (900009).

The spelling of 2521261 in words is "two million, five hundred twenty-one thousand, two hundred sixty-one".