2640139 has 2 divisors, whose sum is σ = 2640140. Its totient is φ = 2640138.

The previous prime is 2640137. The next prime is 2640163. The reversal of 2640139 is 9310462.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 2640139 - 2¹ = 2640137 is a prime.

Together with 2640137, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (2640137) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1320069 + 1320070.

It is an arithmetic number, because the mean of its divisors is an integer number (1320070).

2^2640139 is an apocalyptic number.

2640139 is a deficient number, since it is larger than the sum of its proper divisors (1).

2640139 is an equidigital number, since it uses as much as digits as its factorization.

2640139 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1296, while the sum is 25.

The square root of 2640139 is about 1624.8504546573. The cubic root of 2640139 is about 138.2108901860.

The spelling of 2640139 in words is "two million, six hundred forty thousand, one hundred thirty-nine".