1809966 has 32 divisors (see below), whose sum is σ = 3852288. Its totient is φ = 565920.

The previous prime is 1809953. The next prime is 1809967. The reversal of 1809966 is 6699081.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1809967) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 6751 + ... + 7013.

It is an arithmetic number, because the mean of its divisors is an integer number (120384).

2^1809966 is an apocalyptic number.

1809966 is an abundant number, since it is smaller than the sum of its proper divisors (2042322).

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

1809966 is a wasteful number, since it uses less digits than its factorization.

1809966 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 336.

The product of its (nonzero) digits is 23328, while the sum is 39.

The square root of 1809966 is about 1345.3497686475. The cubic root of 1809966 is about 121.8681276861.

It can be divided in two parts, 1809 and 966, that added together give a triangular number (2775 = T₇₄).

The spelling of 1809966 in words is "one million, eight hundred nine thousand, nine hundred sixty-six".