1806157 has 4 divisors (see below), whose sum is σ = 1808860. Its totient is φ = 1803456.

The previous prime is 1806151. The next prime is 1806191. The reversal of 1806157 is 7516081.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It can be written as a sum of positive squares in 2 ways, for example, as 203401 + 1602756 = 451^2 + 1266^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1806157 is a prime.

It is a Duffinian number.

1806157 is a lucky number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1806151) 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 3 ways as a sum of consecutive naturals, for example, 469 + ... + 1957.

It is an arithmetic number, because the mean of its divisors is an integer number (452215).

2^1806157 is an apocalyptic number.

It is an amenable number.

1806157 is a deficient number, since it is larger than the sum of its proper divisors (2703).

1806157 is a wasteful number, since it uses less digits than its factorization.

1806157 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2702.

The product of its (nonzero) digits is 1680, while the sum is 28.

The square root of 1806157 is about 1343.9334060883. The cubic root of 1806157 is about 121.7825788035.

The spelling of 1806157 in words is "one million, eight hundred six thousand, one hundred fifty-seven".