1945881 has 24 divisors (see below), whose sum is σ = 3267264. Its totient is φ = 1092960.

The previous prime is 1945873. The next prime is 1945883. The reversal of 1945881 is 1885491.

It is not a de Polignac number, because 1945881 - 2³ = 1945873 is a prime.

It is a super-2 number, since 2×1945881² = 7572905732322, which contains 22 as substring.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (1945883) 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 23 ways as a sum of consecutive naturals, for example, 3991 + ... + 4451.

It is an arithmetic number, because the mean of its divisors is an integer number (136136).

2^1945881 is an apocalyptic number.

It is an amenable number.

1945881 is a deficient number, since it is larger than the sum of its proper divisors (1321383).

1945881 is a wasteful number, since it uses less digits than its factorization.

1945881 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 541 (or 538 counting only the distinct ones).

The product of its digits is 11520, while the sum is 36.

The square root of 1945881 is about 1394.9483861419. The cubic root of 1945881 is about 124.8452698811.

The spelling of 1945881 in words is "one million, nine hundred forty-five thousand, eight hundred eighty-one".