1987139 has 16 divisors (see below), whose sum is σ = 2509056. Its totient is φ = 1528800.

The previous prime is 1987127. The next prime is 1987151. The reversal of 1987139 is 9317891.

It is an interprime number because it is at equal distance from previous prime (1987127) and next prime (1987151).

It is not a de Polignac number, because 1987139 - 2⁴ = 1987123 is a prime.

It is not an unprimeable number, because it can be changed into a prime (1987189) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 9989 + ... + 10185.

It is an arithmetic number, because the mean of its divisors is an integer number (156816).

2^1987139 is an apocalyptic number.

1987139 is a deficient number, since it is larger than the sum of its proper divisors (521917).

1987139 is a wasteful number, since it uses less digits than its factorization.

1987139 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 346.

The product of its digits is 13608, while the sum is 38.

The square root of 1987139 is about 1409.6591786670. The cubic root of 1987139 is about 125.7214599531.

It can be divided in two parts, 198 and 7139, that added together give a palindrome (7337).

The spelling of 1987139 in words is "one million, nine hundred eighty-seven thousand, one hundred thirty-nine".