1091399071 has 8 divisors (see below), whose sum is σ = 1247968800. Its totient is φ = 934993248.

The previous prime is 1091399053. The next prime is 1091399077. The reversal of 1091399071 is 1709931901.

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

It is not a de Polignac number, because 1091399071 - 2⁷ = 1091398943 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 (1091399077) 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, 26356 + ... + 53641.

It is an arithmetic number, because the mean of its divisors is an integer number (155996100).

Almost surely, 2^1091399071 is an apocalyptic number.

1091399071 is a deficient number, since it is larger than the sum of its proper divisors (156569729).

1091399071 is an equidigital number, since it uses as much as digits as its factorization.

1091399071 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 81953.

The product of its (nonzero) digits is 15309, while the sum is 40.

The square root of 1091399071 is about 33036.3295630734. The cubic root of 1091399071 is about 1029.5825973914.

The spelling of 1091399071 in words is "one billion, ninety-one million, three hundred ninety-nine thousand, seventy-one".