1945905 has 32 divisors (see below), whose sum is σ = 3556224. Its totient is φ = 900096.

The previous prime is 1945903. The next prime is 1945913. The reversal of 1945905 is 5095491.

It is not a de Polignac number, because 1945905 - 2¹ = 1945903 is a prime.

It is not an unprimeable number, because it can be changed into a prime (1945903) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 3022 + ... + 3608.

It is an arithmetic number, because the mean of its divisors is an integer number (111132).

2^1945905 is an apocalyptic number.

1945905 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

1945905 is a deficient number, since it is larger than the sum of its proper divisors (1610319).

1945905 is a wasteful number, since it uses less digits than its factorization.

1945905 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 625.

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

The square root of 1945905 is about 1394.9569885842. The cubic root of 1945905 is about 124.8457831489.

It can be divided in two parts, 1945 and 905, that added together give a triangular number (2850 = T₇₅).

The spelling of 1945905 in words is "one million, nine hundred forty-five thousand, nine hundred five".