1093801991 has 2 divisors, whose sum is σ = 1093801992. Its totient is φ = 1093801990.

The previous prime is 1093801987. The next prime is 1093801993. The reversal of 1093801991 is 1991083901.

It is a happy number.

It is a strong prime.

It is an emirp because it is prime and its reverse (1991083901) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1093801991 - 2² = 1093801987 is a prime.

It is a Sophie Germain prime.

Together with 1093801993, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1093801993) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 546900995 + 546900996.

It is an arithmetic number, because the mean of its divisors is an integer number (546900996).

Almost surely, 2^1093801991 is an apocalyptic number.

1093801991 is a deficient number, since it is larger than the sum of its proper divisors (1).

1093801991 is an equidigital number, since it uses as much as digits as its factorization.

1093801991 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 17496, while the sum is 41.

The square root of 1093801991 is about 33072.6774090033. The cubic root of 1093801991 is about 1030.3376500073.

The spelling of 1093801991 in words is "one billion, ninety-three million, eight hundred one thousand, nine hundred ninety-one".