2188639 has 2 divisors, whose sum is σ = 2188640. Its totient is φ = 2188638.

The previous prime is 2188609. The next prime is 2188651. The reversal of 2188639 is 9368812.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 2188639 - 2⁵ = 2188607 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 2188598 and 2188607.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (2188609) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1094319 + 1094320.

It is an arithmetic number, because the mean of its divisors is an integer number (1094320).

2^2188639 is an apocalyptic number.

2188639 is a deficient number, since it is larger than the sum of its proper divisors (1).

2188639 is an equidigital number, since it uses as much as digits as its factorization.

2188639 is an evil number, because the sum of its binary digits is even.

The product of its digits is 20736, while the sum is 37.

The square root of 2188639 is about 1479.4049479436. The cubic root of 2188639 is about 129.8348791161.

The spelling of 2188639 in words is "two million, one hundred eighty-eight thousand, six hundred thirty-nine".