1187191 has 8 divisors (see below), whose sum is σ = 1257984. Its totient is φ = 1118040.

The previous prime is 1187189. The next prime is 1187201. The reversal of 1187191 is 1917811.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 1187191 - 2¹ = 1187189 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 (1187111) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1270 + ... + 1996.

It is an arithmetic number, because the mean of its divisors is an integer number (157248).

2^1187191 is an apocalyptic number.

1187191 is a deficient number, since it is larger than the sum of its proper divisors (70793).

1187191 is an equidigital number, since it uses as much as digits as its factorization.

1187191 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 821.

The product of its digits is 504, while the sum is 28.

The square root of 1187191 is about 1089.5829477373. The cubic root of 1187191 is about 105.8864037605.

It can be divided in two parts, 1187 and 191, that added together give a triangular number (1378 = T₅₂).

The spelling of 1187191 in words is "one million, one hundred eighty-seven thousand, one hundred ninety-one".