1971889894 has 16 divisors (see below), whose sum is σ = 3189265632. Its totient is φ = 908987328.

The previous prime is 1971889861. The next prime is 1971889903. The reversal of 1971889894 is 4989881791.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 24679 + ... + 67474.

It is an arithmetic number, because the mean of its divisors is an integer number (199329102).

Almost surely, 2^1971889894 is an apocalyptic number.

1971889894 is a deficient number, since it is larger than the sum of its proper divisors (1217375738).

1971889894 is a wasteful number, since it uses less digits than its factorization.

1971889894 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 92991.

The product of its digits is 10450944, while the sum is 64.

The square root of 1971889894 is about 44405.9668738335. The cubic root of 1971889894 is about 1253.9904250376.

The spelling of 1971889894 in words is "one billion, nine hundred seventy-one million, eight hundred eighty-nine thousand, eight hundred ninety-four".