1968138 has 20 divisors (see below), whose sum is σ = 4410450. Its totient is φ = 655992.

The previous prime is 1968137. The next prime is 1968139. The reversal of 1968138 is 8318691.

It is an interprime number because it is at equal distance from previous prime (1968137) and next prime (1968139).

It can be written as a sum of positive squares in only one way, i.e., 1108809 + 859329 = 1053^2 + 927^2 .

It is an Ulam number.

It is not an unprimeable number, because it can be changed into a prime (1968137) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 9 ways as a sum of consecutive naturals, for example, 5913 + ... + 6236.

2^1968138 is an apocalyptic number.

1968138 is a gapful number since it is divisible by the number (18) formed by its first and last digit.

1968138 is an abundant number, since it is smaller than the sum of its proper divisors (2442312).

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

1968138 is a wasteful number, since it uses less digits than its factorization.

1968138 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12163 (or 12154 counting only the distinct ones).

The product of its digits is 10368, while the sum is 36.

The square root of 1968138 is about 1402.9034179159. The cubic root of 1968138 is about 125.3194601993.

The spelling of 1968138 in words is "one million, nine hundred sixty-eight thousand, one hundred thirty-eight".