1949281809091 has 2 divisors, whose sum is σ = 1949281809092. Its totient is φ = 1949281809090.

The previous prime is 1949281809089. The next prime is 1949281809169. The reversal of 1949281809091 is 1909081829491.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 1949281809091 - 2¹ = 1949281809089 is a prime.

Together with 1949281809089, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (1949281809791) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 974640904545 + 974640904546.

It is an arithmetic number, because the mean of its divisors is an integer number (974640904546).

Almost surely, 2^{1949281809091} is an apocalyptic number.

1949281809091 is a deficient number, since it is larger than the sum of its proper divisors (1).

1949281809091 is an equidigital number, since it uses as much as digits as its factorization.

1949281809091 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 3359232, while the sum is 61.

The spelling of 1949281809091 in words is "one trillion, nine hundred forty-nine billion, two hundred eighty-one million, eight hundred nine thousand, ninety-one".