2138987 has 2 divisors, whose sum is σ = 2138988. Its totient is φ = 2138986.

The previous prime is 2138971. The next prime is 2138989. The reversal of 2138987 is 7898312.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 2138987 - 2⁴ = 2138971 is a prime.

Together with 2138989, it forms a pair of twin primes.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 2138987.

It is not a weakly prime, because it can be changed into another prime (2138989) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1069493 + 1069494.

It is an arithmetic number, because the mean of its divisors is an integer number (1069494).

2^2138987 is an apocalyptic number.

2138987 is a deficient number, since it is larger than the sum of its proper divisors (1).

2138987 is an equidigital number, since it uses as much as digits as its factorization.

2138987 is an evil number, because the sum of its binary digits is even.

The product of its digits is 24192, while the sum is 38.

The square root of 2138987 is about 1462.5276065771. The cubic root of 2138987 is about 128.8455375355.

It can be divided in two parts, 2138 and 987, that added together give a 5-th power (3125 = 5⁵).

The spelling of 2138987 in words is "two million, one hundred thirty-eight thousand, nine hundred eighty-seven".