1911281 has 2 divisors, whose sum is σ = 1911282. Its totient is φ = 1911280.

The previous prime is 1911269. The next prime is 1911289. The reversal of 1911281 is 1821191.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1677025 + 234256 = 1295^2 + 484^2 .

It is an emirp because it is prime and its reverse (1821191) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1911281 - 2¹⁰ = 1910257 is a prime.

It is a super-2 number, since 2×1911281² = 7305990121922, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (1911289) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 955640 + 955641.

It is an arithmetic number, because the mean of its divisors is an integer number (955641).

2^1911281 is an apocalyptic number.

It is an amenable number.

1911281 is a deficient number, since it is larger than the sum of its proper divisors (1).

1911281 is an equidigital number, since it uses as much as digits as its factorization.

1911281 is an evil number, because the sum of its binary digits is even.

The product of its digits is 144, while the sum is 23.

The square root of 1911281 is about 1382.4908679626. The cubic root of 1911281 is about 124.1008761166.

The spelling of 1911281 in words is "one million, nine hundred eleven thousand, two hundred eighty-one".