11111681947 has 2 divisors, whose sum is σ = 11111681948. Its totient is φ = 11111681946.

The previous prime is 11111681909. The next prime is 11111681989. The reversal of 11111681947 is 74918611111.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-11111681947 is a prime.

It is not a weakly prime, because it can be changed into another prime (11111681047) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5555840973 + 5555840974.

It is an arithmetic number, because the mean of its divisors is an integer number (5555840974).

Almost surely, 2^11111681947 is an apocalyptic number.

11111681947 is a deficient number, since it is larger than the sum of its proper divisors (1).

11111681947 is an equidigital number, since it uses as much as digits as its factorization.

11111681947 is an evil number, because the sum of its binary digits is even.

The product of its digits is 12096, while the sum is 40.

The spelling of 11111681947 in words is "eleven billion, one hundred eleven million, six hundred eighty-one thousand, nine hundred forty-seven".