2140639 has 4 divisors (see below), whose sum is σ = 2145256. Its totient is φ = 2136024.

The previous prime is 2140637. The next prime is 2140681. The reversal of 2140639 is 9360412.

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

It is a cyclic number.

It is not a de Polignac number, because 2140639 - 2¹ = 2140637 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2140631) 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, 1524 + ... + 2569.

It is an arithmetic number, because the mean of its divisors is an integer number (536314).

2^2140639 is an apocalyptic number.

2140639 is a deficient number, since it is larger than the sum of its proper divisors (4617).

2140639 is an equidigital number, since it uses as much as digits as its factorization.

2140639 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4616.

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

The square root of 2140639 is about 1463.0922732350. The cubic root of 2140639 is about 128.8786993475.

The spelling of 2140639 in words is "two million, one hundred forty thousand, six hundred thirty-nine".