2542821 has 4 divisors (see below), whose sum is σ = 3390432. Its totient is φ = 1695212.

The previous prime is 2542817. The next prime is 2542823. The reversal of 2542821 is 1282452.

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 not a de Polignac number, because 2542821 - 2² = 2542817 is a prime.

It is a D-number.

It is a junction number, because it is equal to n+sod(n) for n = 2542791 and 2542800.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2542823) 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, 423801 + ... + 423806.

It is an arithmetic number, because the mean of its divisors is an integer number (847608).

2^2542821 is an apocalyptic number.

It is an amenable number.

2542821 is a deficient number, since it is larger than the sum of its proper divisors (847611).

2542821 is an equidigital number, since it uses as much as digits as its factorization.

2542821 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 847610.

The product of its digits is 1280, while the sum is 24.

The square root of 2542821 is about 1594.6225258662. The cubic root of 2542821 is about 136.4913920695.

The spelling of 2542821 in words is "two million, five hundred forty-two thousand, eight hundred twenty-one".