1381987 has 8 divisors (see below), whose sum is σ = 1455552. Its totient is φ = 1310400.

The previous prime is 1381979. The next prime is 1381993. The reversal of 1381987 is 7891831.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 1381987 - 2³ = 1381979 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (37).

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1381907) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1062 + ... + 1972.

It is an arithmetic number, because the mean of its divisors is an integer number (181944).

2^1381987 is an apocalyptic number.

1381987 is a deficient number, since it is larger than the sum of its proper divisors (73565).

1381987 is an equidigital number, since it uses as much as digits as its factorization.

1381987 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 989.

The product of its digits is 12096, while the sum is 37.

The square root of 1381987 is about 1175.5794315996. The cubic root of 1381987 is about 111.3870372896.

The spelling of 1381987 in words is "one million, three hundred eighty-one thousand, nine hundred eighty-seven".