10668671991 has 24 divisors (see below), whose sum is σ = 15847650000. Its totient is φ = 6913306752.

The previous prime is 10668671977. The next prime is 10668672013. The reversal of 10668671991 is 19917686601.

It is a happy number.

It is not a de Polignac number, because 10668671991 - 2⁹ = 10668671479 is a prime.

It is a super-2 number, since 2×10668671991² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (10668671971) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 65616 + ... + 160133.

It is an arithmetic number, because the mean of its divisors is an integer number (660318750).

Almost surely, 2^10668671991 is an apocalyptic number.

10668671991 is a deficient number, since it is larger than the sum of its proper divisors (5178978009).

10668671991 is a wasteful number, since it uses less digits than its factorization.

10668671991 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 225903 (or 225900 counting only the distinct ones).

The product of its (nonzero) digits is 979776, while the sum is 54.

The spelling of 10668671991 in words is "ten billion, six hundred sixty-eight million, six hundred seventy-one thousand, nine hundred ninety-one".