11897894909 has 2 divisors, whose sum is σ = 11897894910. Its totient is φ = 11897894908.

The previous prime is 11897894843. The next prime is 11897894923. The reversal of 11897894909 is 90949879811.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 11881654009 + 16240900 = 109003^2 + 4030^2 .

It is a cyclic number.

It is not a de Polignac number, because 11897894909 - 2⁸ = 11897894653 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (11897894959) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5948947454 + 5948947455.

It is an arithmetic number, because the mean of its divisors is an integer number (5948947455).

Almost surely, 2^11897894909 is an apocalyptic number.

It is an amenable number.

11897894909 is a deficient number, since it is larger than the sum of its proper divisors (1).

11897894909 is an equidigital number, since it uses as much as digits as its factorization.

11897894909 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 11757312, while the sum is 65.

The spelling of 11897894909 in words is "eleven billion, eight hundred ninety-seven million, eight hundred ninety-four thousand, nine hundred nine".