1881659945 has 16 divisors (see below), whose sum is σ = 2523346560. Its totient is φ = 1335100800.

The previous prime is 1881659939. The next prime is 1881659947. The reversal of 1881659945 is 5499561881.

It is not a de Polignac number, because 1881659945 - 2¹⁶ = 1881594409 is a prime.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (1881659947) 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, 414965 + ... + 419474.

It is an arithmetic number, because the mean of its divisors is an integer number (157709160).

Almost surely, 2^1881659945 is an apocalyptic number.

It is an amenable number.

1881659945 is a deficient number, since it is larger than the sum of its proper divisors (641686615).

1881659945 is a wasteful number, since it uses less digits than its factorization.

1881659945 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 834496.

The product of its digits is 3110400, while the sum is 56.

The square root of 1881659945 is about 43378.1044422183. The cubic root of 1881659945 is about 1234.5642974507.

The spelling of 1881659945 in words is "one billion, eight hundred eighty-one million, six hundred fifty-nine thousand, nine hundred forty-five".