1891434481 has 2 divisors, whose sum is σ = 1891434482. Its totient is φ = 1891434480.

The previous prime is 1891434443. The next prime is 1891434499. The reversal of 1891434481 is 1844341981.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1568872881 + 322561600 = 39609^2 + 17960^2 .

It is an emirp because it is prime and its reverse (1844341981) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1891434481 - 2¹⁵ = 1891401713 is a prime.

It is a super-2 number, since 2×1891434481² = 7155048791831478722, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (1891234481) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 945717240 + 945717241.

It is an arithmetic number, because the mean of its divisors is an integer number (945717241).

Almost surely, 2^1891434481 is an apocalyptic number.

It is an amenable number.

1891434481 is a deficient number, since it is larger than the sum of its proper divisors (1).

1891434481 is an equidigital number, since it uses as much as digits as its factorization.

1891434481 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 110592, while the sum is 43.

The square root of 1891434481 is about 43490.6252081986. The cubic root of 1891434481 is about 1236.6983100699.

The spelling of 1891434481 in words is "one billion, eight hundred ninety-one million, four hundred thirty-four thousand, four hundred eighty-one".