1311020191 has 8 divisors (see below), whose sum is σ = 1418036480. Its totient is φ = 1204885152.

The previous prime is 1311020167. The next prime is 1311020201. The reversal of 1311020191 is 1910201131.

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 1311020191 - 2¹¹ = 1311018143 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 (1311020591) 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, 217215 + ... + 223168.

It is an arithmetic number, because the mean of its divisors is an integer number (177254560).

Almost surely, 2^1311020191 is an apocalyptic number.

1311020191 is a deficient number, since it is larger than the sum of its proper divisors (107016289).

1311020191 is a wasteful number, since it uses less digits than its factorization.

1311020191 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 440625.

The product of its (nonzero) digits is 54, while the sum is 19.

The square root of 1311020191 is about 36208.0128010362. The cubic root of 1311020191 is about 1094.4681475733.

The spelling of 1311020191 in words is "one billion, three hundred eleven million, twenty thousand, one hundred ninety-one".