11991361671 has 48 divisors (see below), whose sum is σ = 17997033600. Its totient is φ = 7689629376.

The previous prime is 11991361651. The next prime is 11991361693. The reversal of 11991361671 is 17616319911.

11991361671 is a `hidden beast` number, since 1 + 19 + 9 + 13 + 616 + 7 + 1 = 666.

It is not a de Polignac number, because 11991361671 - 2⁹ = 11991361159 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (11991361601) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 5502060 + ... + 5504238.

It is an arithmetic number, because the mean of its divisors is an integer number (374938200).

Almost surely, 2^11991361671 is an apocalyptic number.

11991361671 is a deficient number, since it is larger than the sum of its proper divisors (6005671929).

11991361671 is a wasteful number, since it uses less digits than its factorization.

11991361671 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2460 (or 2457 counting only the distinct ones).

The product of its digits is 61236, while the sum is 45.

The spelling of 11991361671 in words is "eleven billion, nine hundred ninety-one million, three hundred sixty-one thousand, six hundred seventy-one".