1906605 has 32 divisors (see below), whose sum is σ = 3513600. Its totient is φ = 979776.

The previous prime is 1906603. The next prime is 1906607. The reversal of 1906605 is 5066091.

It is an interprime number because it is at equal distance from previous prime (1906603) and next prime (1906607).

It is not a de Polignac number, because 1906605 - 2¹ = 1906603 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1906603) 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 31 ways as a sum of consecutive naturals, for example, 3672 + ... + 4158.

It is an arithmetic number, because the mean of its divisors is an integer number (109800).

2^1906605 is an apocalyptic number.

1906605 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

1906605 is a deficient number, since it is larger than the sum of its proper divisors (1606995).

1906605 is a wasteful number, since it uses less digits than its factorization.

1906605 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 530 (or 524 counting only the distinct ones).

The product of its (nonzero) digits is 1620, while the sum is 27.

The square root of 1906605 is about 1380.7986819229. The cubic root of 1906605 is about 123.9995881013. Note that the first 3 decimals are identical.

The spelling of 1906605 in words is "one million, nine hundred six thousand, six hundred five".