1905945 has 16 divisors (see below), whose sum is σ = 3100992. Its totient is φ = 999360.

The previous prime is 1905923. The next prime is 1905979. The reversal of 1905945 is 5495091.

It is not a de Polignac number, because 1905945 - 2⁸ = 1905689 is a prime.

It is a Curzon number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 127 + ... + 1956.

It is an arithmetic number, because the mean of its divisors is an integer number (193812).

2^1905945 is an apocalyptic number.

1905945 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

1905945 is a deficient number, since it is larger than the sum of its proper divisors (1195047).

1905945 is a wasteful number, since it uses less digits than its factorization.

1905945 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2152.

The product of its (nonzero) digits is 8100, while the sum is 33.

The square root of 1905945 is about 1380.5596691197. The cubic root of 1905945 is about 123.9852783425.

It can be divided in two parts, 1905 and 945, that added together give a triangular number (2850 = T₇₅).

The spelling of 1905945 in words is "one million, nine hundred five thousand, nine hundred forty-five".