1091212971 has 4 divisors (see below), whose sum is σ = 1454950632. Its totient is φ = 727475312.

The previous prime is 1091212961. The next prime is 1091212999. The reversal of 1091212971 is 1792121901.

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

It is a cyclic number.

It is not a de Polignac number, because 1091212971 - 2⁵ = 1091212939 is a prime.

It is not an unprimeable number, because it can be changed into a prime (1091212901) 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, 181868826 + ... + 181868831.

It is an arithmetic number, because the mean of its divisors is an integer number (363737658).

Almost surely, 2^1091212971 is an apocalyptic number.

1091212971 is a deficient number, since it is larger than the sum of its proper divisors (363737661).

1091212971 is an equidigital number, since it uses as much as digits as its factorization.

1091212971 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 363737660.

The product of its (nonzero) digits is 2268, while the sum is 33.

The square root of 1091212971 is about 33033.5128468045. The cubic root of 1091212971 is about 1029.5240742786.

The spelling of 1091212971 in words is "one billion, ninety-one million, two hundred twelve thousand, nine hundred seventy-one".