2642639 has 2 divisors, whose sum is σ = 2642640. Its totient is φ = 2642638.

The previous prime is 2642621. The next prime is 2642693. The reversal of 2642639 is 9362462.

2642639 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

Together with next prime (2642693) it forms an Ormiston pair, because they use the same digits, order apart.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 2642639 - 2⁸ = 2642383 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (2642609) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1321319 + 1321320.

It is an arithmetic number, because the mean of its divisors is an integer number (1321320).

2^2642639 is an apocalyptic number.

2642639 is a deficient number, since it is larger than the sum of its proper divisors (1).

2642639 is an equidigital number, since it uses as much as digits as its factorization.

2642639 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 15552, while the sum is 32.

The square root of 2642639 is about 1625.6195741932. The cubic root of 2642639 is about 138.2545013015.

It can be divided in two parts, 264 and 2639, that multiplied together give a palindrome (696696).

The spelling of 2642639 in words is "two million, six hundred forty-two thousand, six hundred thirty-nine".