1987439 has 2 divisors, whose sum is σ = 1987440. Its totient is φ = 1987438.

The previous prime is 1987429. The next prime is 1987451. The reversal of 1987439 is 9347891.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 1987439 - 2¹² = 1983343 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 1987396 and 1987405.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1987429) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 993719 + 993720.

It is an arithmetic number, because the mean of its divisors is an integer number (993720).

2^1987439 is an apocalyptic number.

1987439 is a deficient number, since it is larger than the sum of its proper divisors (1).

1987439 is an equidigital number, since it uses as much as digits as its factorization.

1987439 is an evil number, because the sum of its binary digits is even.

The product of its digits is 54432, while the sum is 41.

The square root of 1987439 is about 1409.7655833507. The cubic root of 1987439 is about 125.7277863920.

The spelling of 1987439 in words is "one million, nine hundred eighty-seven thousand, four hundred thirty-nine".