1945040891 has 2 divisors, whose sum is σ = 1945040892. Its totient is φ = 1945040890.

The previous prime is 1945040857. The next prime is 1945040893. The reversal of 1945040891 is 1980405491.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 1945040891 - 2¹⁰ = 1945039867 is a prime.

It is a super-3 number, since 3×1945040891³ (a number of 29 digits) contains 333 as substring.

Together with 1945040893, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (1945040893) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 972520445 + 972520446.

It is an arithmetic number, because the mean of its divisors is an integer number (972520446).

Almost surely, 2^1945040891 is an apocalyptic number.

1945040891 is a deficient number, since it is larger than the sum of its proper divisors (1).

1945040891 is an equidigital number, since it uses as much as digits as its factorization.

1945040891 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 51840, while the sum is 41.

The square root of 1945040891 is about 44102.6177340983. The cubic root of 1945040891 is about 1248.2730051699.

The spelling of 1945040891 in words is "one billion, nine hundred forty-five million, forty thousand, eight hundred ninety-one".