1667889 has 12 divisors (see below), whose sum is σ = 2461056. Its totient is φ = 1087992.

The previous prime is 1667881. The next prime is 1667899. The reversal of 1667889 is 9887661.

It is a happy number.

It is not a de Polignac number, because 1667889 - 2³ = 1667881 is a prime.

It is a plaindrome in base 10.

It is not an unprimeable number, because it can be changed into a prime (1667881) 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, 1549 + ... + 2394.

It is an arithmetic number, because the mean of its divisors is an integer number (205088).

2^1667889 is an apocalyptic number.

It is an amenable number.

1667889 is a deficient number, since it is larger than the sum of its proper divisors (793167).

1667889 is a wasteful number, since it uses less digits than its factorization.

1667889 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3996 (or 3993 counting only the distinct ones).

The product of its digits is 145152, while the sum is 45.

The square root of 1667889 is about 1291.4677696327. The cubic root of 1667889 is about 118.5920877951.

It can be divided in two parts, 1667 and 889, that added together give a triangular number (2556 = T₇₁).

The spelling of 1667889 in words is "one million, six hundred sixty-seven thousand, eight hundred eighty-nine".