19961289172 has 96 divisors (see below), whose sum is σ = 39327724800. Its totient is φ = 8862543360.

The previous prime is 19961289149. The next prime is 19961289203. The reversal of 19961289172 is 27198216991.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 48804904 + ... + 48805312.

It is an arithmetic number, because the mean of its divisors is an integer number (409663800).

Almost surely, 2^19961289172 is an apocalyptic number.

It is an amenable number.

19961289172 is a deficient number, since it is larger than the sum of its proper divisors (19366435628).

19961289172 is a wasteful number, since it uses less digits than its factorization.

19961289172 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 638 (or 614 counting only the distinct ones).

The product of its digits is 979776, while the sum is 55.

The spelling of 19961289172 in words is "nineteen billion, nine hundred sixty-one million, two hundred eighty-nine thousand, one hundred seventy-two".