1891717172 has 12 divisors (see below), whose sum is σ = 3311024640. Its totient is φ = 945710136.

The previous prime is 1891717171. The next prime is 1891717187. The reversal of 1891717172 is 2717171981.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1891717171) 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 3 ways as a sum of consecutive naturals, for example, 5438 + ... + 61749.

It is an arithmetic number, because the mean of its divisors is an integer number (275918720).

Almost surely, 2^1891717172 is an apocalyptic number.

It is an amenable number.

1891717172 is a deficient number, since it is larger than the sum of its proper divisors (1419307468).

1891717172 is a wasteful number, since it uses less digits than its factorization.

1891717172 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 74230 (or 74228 counting only the distinct ones).

The product of its digits is 49392, while the sum is 44.

The square root of 1891717172 is about 43493.8751090312. The cubic root of 1891717172 is about 1236.7599187008.

The spelling of 1891717172 in words is "one billion, eight hundred ninety-one million, seven hundred seventeen thousand, one hundred seventy-two".