1913605 has 16 divisors (see below), whose sum is σ = 2488320. Its totient is φ = 1407232.

The previous prime is 1913581. The next prime is 1913609. The reversal of 1913605 is 5063191.

It is a cyclic number.

It is not a de Polignac number, because 1913605 - 2⁷ = 1913477 is a prime.

1913605 is a lucky number.

It is a self number, because there is not a number n which added to its sum of digits gives 1913605.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1913609) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 3756 + ... + 4234.

It is an arithmetic number, because the mean of its divisors is an integer number (155520).

2^1913605 is an apocalyptic number.

1913605 is the 799-th octagonal number.

It is an amenable number.

1913605 is a deficient number, since it is larger than the sum of its proper divisors (574715).

1913605 is a wasteful number, since it uses less digits than its factorization.

1913605 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 548.

The product of its (nonzero) digits is 810, while the sum is 25.

The square root of 1913605 is about 1383.3311244962. The cubic root of 1913605 is about 124.1511554176.

Adding to 1913605 its reverse (5063191), we get a palindrome (6976796).

The spelling of 1913605 in words is "one million, nine hundred thirteen thousand, six hundred five".