1806690 has 16 divisors (see below), whose sum is σ = 4336128. Its totient is φ = 481776.

The previous prime is 1806689. The next prime is 1806697. The reversal of 1806690 is 966081.

It is a super-2 number, since 2×1806690² = 6528257512200, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (30), and also a Moran number because the ratio is a prime number: 60223 = 1806690 / (1 + 8 + 0 + 6 + 6 + 9 + 0).

It is an Ulam number.

It is not an unprimeable number, because it can be changed into a prime (1806697) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 30082 + ... + 30141.

It is an arithmetic number, because the mean of its divisors is an integer number (271008).

2^1806690 is an apocalyptic number.

1806690 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

1806690 is an abundant number, since it is smaller than the sum of its proper divisors (2529438).

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

1806690 is a wasteful number, since it uses less digits than its factorization.

1806690 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 60233.

The product of its (nonzero) digits is 2592, while the sum is 30.

The square root of 1806690 is about 1344.1316899768. The cubic root of 1806690 is about 121.7945570406.

The spelling of 1806690 in words is "one million, eight hundred six thousand, six hundred ninety".