1381998 has 24 divisors (see below), whose sum is σ = 2939832. Its totient is φ = 433024.

The previous prime is 1381997. The next prime is 1381999. The reversal of 1381998 is 8991831.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (1381997) and next prime (1381999).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1381993) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1336 + ... + 2132.

It is an arithmetic number, because the mean of its divisors is an integer number (122493).

2^1381998 is an apocalyptic number.

1381998 is an abundant number, since it is smaller than the sum of its proper divisors (1557834).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1381998 is a wasteful number, since it uses less digits than its factorization.

1381998 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 836 (or 819 counting only the distinct ones).

The product of its digits is 15552, while the sum is 39.

The square root of 1381998 is about 1175.5841101342. The cubic root of 1381998 is about 111.3873328192.

The spelling of 1381998 in words is "one million, three hundred eighty-one thousand, nine hundred ninety-eight".