1669428 has 36 divisors (see below), whose sum is σ = 4280640. Its totient is φ = 548496.

The previous prime is 1669427. The next prime is 1669433. The reversal of 1669428 is 8249661.

It is a tau number, because it is divible by the number of its divisors (36).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a junction number, because it is equal to n+sod(n) for n = 1669392 and 1669401.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1669427) 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, 2551 + ... + 3137.

2^1669428 is an apocalyptic number.

1669428 is a gapful number since it is divisible by the number (18) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1669428, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2140320).

1669428 is an abundant number, since it is smaller than the sum of its proper divisors (2611212).

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

1669428 is a wasteful number, since it uses less digits than its factorization.

1669428 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 676 (or 671 counting only the distinct ones).

The product of its digits is 20736, while the sum is 36.

The square root of 1669428 is about 1292.0634659335. The cubic root of 1669428 is about 118.6285524750.

The spelling of 1669428 in words is "one million, six hundred sixty-nine thousand, four hundred twenty-eight".