1188664860391 has 16 divisors (see below), whose sum is σ = 1213669435104. Its totient is φ = 1163884068864.

The previous prime is 1188664860389. The next prime is 1188664860403. The reversal of 1188664860391 is 1930684668811.

It is a happy number.

It is a cyclic number.

It is not a de Polignac number, because 1188664860391 - 2¹ = 1188664860389 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1188664860091) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 15699261 + ... + 15774793.

It is an arithmetic number, because the mean of its divisors is an integer number (75854339694).

Almost surely, 2^{1188664860391} is an apocalyptic number.

1188664860391 is a deficient number, since it is larger than the sum of its proper divisors (25004574713).

1188664860391 is a wasteful number, since it uses less digits than its factorization.

1188664860391 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 77010.

The product of its (nonzero) digits is 11943936, while the sum is 61.

The spelling of 1188664860391 in words is "one trillion, one hundred eighty-eight billion, six hundred sixty-four million, eight hundred sixty thousand, three hundred ninety-one".