2687639 has 2 divisors, whose sum is σ = 2687640. Its totient is φ = 2687638.

The previous prime is 2687621. The next prime is 2687647. The reversal of 2687639 is 9367862.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 2687639 - 2⁸ = 2687383 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 2687596 and 2687605.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (2687609) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1343819 + 1343820.

It is an arithmetic number, because the mean of its divisors is an integer number (1343820).

2^2687639 is an apocalyptic number.

2687639 is a deficient number, since it is larger than the sum of its proper divisors (1).

2687639 is an equidigital number, since it uses as much as digits as its factorization.

2687639 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 108864, while the sum is 41.

The square root of 2687639 is about 1639.4020251299. The cubic root of 2687639 is about 139.0348410842.

The spelling of 2687639 in words is "two million, six hundred eighty-seven thousand, six hundred thirty-nine".