11381631817 has 2 divisors, whose sum is σ = 11381631818. Its totient is φ = 11381631816.

The previous prime is 11381631797. The next prime is 11381631829. The reversal of 11381631817 is 71813618311.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 9941884681 + 1439747136 = 99709^2 + 37944^2 .

It is a cyclic number.

It is not a de Polignac number, because 11381631817 - 2⁷ = 11381631689 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 11381631817.

It is not a weakly prime, because it can be changed into another prime (11381631887) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5690815908 + 5690815909.

It is an arithmetic number, because the mean of its divisors is an integer number (5690815909).

Almost surely, 2^11381631817 is an apocalyptic number.

It is an amenable number.

11381631817 is a deficient number, since it is larger than the sum of its proper divisors (1).

11381631817 is an equidigital number, since it uses as much as digits as its factorization.

11381631817 is an evil number, because the sum of its binary digits is even.

The product of its digits is 24192, while the sum is 40.

The spelling of 11381631817 in words is "eleven billion, three hundred eighty-one million, six hundred thirty-one thousand, eight hundred seventeen".