1091009281 has 2 divisors, whose sum is σ = 1091009282. Its totient is φ = 1091009280.

The previous prime is 1091009267. The next prime is 1091009299. The reversal of 1091009281 is 1829001901.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 706496400 + 384512881 = 26580^2 + 19609^2 .

It is an emirp because it is prime and its reverse (1829001901) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1091009281 - 2²⁹ = 554138369 is a prime.

It is a super-2 number, since 2×1091009281² = 2380602502456273922, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (1091009251) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 545504640 + 545504641.

It is an arithmetic number, because the mean of its divisors is an integer number (545504641).

Almost surely, 2^1091009281 is an apocalyptic number.

It is an amenable number.

1091009281 is a deficient number, since it is larger than the sum of its proper divisors (1).

1091009281 is an equidigital number, since it uses as much as digits as its factorization.

1091009281 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1296, while the sum is 31.

The square root of 1091009281 is about 33030.4296217897. The cubic root of 1091009281 is about 1029.4600119878.

The spelling of 1091009281 in words is "one billion, ninety-one million, nine thousand, two hundred eighty-one".