1188139971 has 4 divisors (see below), whose sum is σ = 1584186632. Its totient is φ = 792093312.

The previous prime is 1188139963. The next prime is 1188139973. The reversal of 1188139971 is 1799318811.

It is a semiprime because it is the product of two primes.

It is not a de Polignac number, because 1188139971 - 2³ = 1188139963 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 1188139971.

It is not an unprimeable number, because it can be changed into a prime (1188139973) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 198023326 + ... + 198023331.

It is an arithmetic number, because the mean of its divisors is an integer number (396046658).

Almost surely, 2^1188139971 is an apocalyptic number.

1188139971 is a deficient number, since it is larger than the sum of its proper divisors (396046661).

1188139971 is an equidigital number, since it uses as much as digits as its factorization.

1188139971 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 396046660.

The product of its digits is 108864, while the sum is 48.

The square root of 1188139971 is about 34469.4063047219. The cubic root of 1188139971 is about 1059.1460937781.

The spelling of 1188139971 in words is "one billion, one hundred eighty-eight million, one hundred thirty-nine thousand, nine hundred seventy-one".