2639391 has 4 divisors (see below), whose sum is σ = 3519192. Its totient is φ = 1759592.

The previous prime is 2639389. The next prime is 2639393. The reversal of 2639391 is 1939362.

It is a semiprime because it is the product of two primes.

It is an interprime number because it is at equal distance from previous prime (2639389) and next prime (2639393).

It is a cyclic number.

It is not a de Polignac number, because 2639391 - 2¹ = 2639389 is a prime.

It is an Ulam number.

It is a D-number.

2639391 is a lucky number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2639393) 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, 439896 + ... + 439901.

It is an arithmetic number, because the mean of its divisors is an integer number (879798).

2^2639391 is an apocalyptic number.

2639391 is the 1028-th centered pentagonal number.

2639391 is a deficient number, since it is larger than the sum of its proper divisors (879801).

2639391 is an equidigital number, since it uses as much as digits as its factorization.

2639391 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 879800.

The product of its digits is 8748, while the sum is 33.

The square root of 2639391 is about 1624.6202633231. The cubic root of 2639391 is about 138.1978363896.

The spelling of 2639391 in words is "two million, six hundred thirty-nine thousand, three hundred ninety-one".