1378987 has 4 divisors (see below), whose sum is σ = 1382056. Its totient is φ = 1375920.

The previous prime is 1378969. The next prime is 1378997. The reversal of 1378987 is 7898731.

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 1378987 - 2⁷ = 1378859 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1378907) 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, 714 + ... + 1807.

It is an arithmetic number, because the mean of its divisors is an integer number (345514).

2^1378987 is an apocalyptic number.

1378987 is a deficient number, since it is larger than the sum of its proper divisors (3069).

1378987 is an equidigital number, since it uses as much as digits as its factorization.

1378987 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3068.

The product of its digits is 84672, while the sum is 43.

The square root of 1378987 is about 1174.3027718608. The cubic root of 1378987 is about 111.3063797046.

The spelling of 1378987 in words is "one million, three hundred seventy-eight thousand, nine hundred eighty-seven".