1191990347 has 4 divisors (see below), whose sum is σ = 1192825920. Its totient is φ = 1191154776.

The previous prime is 1191990337. The next prime is 1191990361. The reversal of 1191990347 is 7430991911.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 7430991911 = 7 ⋅1061570273.

It is a cyclic number.

It is not a de Polignac number, because 1191990347 - 2¹² = 1191986251 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1191990298 and 1191990307.

It is not an unprimeable number, because it can be changed into a prime (1191990337) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 415643 + ... + 418500.

It is an arithmetic number, because the mean of its divisors is an integer number (298206480).

Almost surely, 2^1191990347 is an apocalyptic number.

1191990347 is a deficient number, since it is larger than the sum of its proper divisors (835573).

1191990347 is an equidigital number, since it uses as much as digits as its factorization.

1191990347 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 835572.

The product of its (nonzero) digits is 61236, while the sum is 44.

The square root of 1191990347 is about 34525.2132071621. The cubic root of 1191990347 is about 1060.2889763328.

The spelling of 1191990347 in words is "one billion, one hundred ninety-one million, nine hundred ninety thousand, three hundred forty-seven".