11813987 has 2 divisors, whose sum is σ = 11813988. Its totient is φ = 11813986.

The previous prime is 11813969. The next prime is 11813993. The reversal of 11813987 is 78931811.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 11813987 - 2⁸ = 11813731 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 11813987.

It is not a weakly prime, because it can be changed into another prime (11813917) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5906993 + 5906994.

It is an arithmetic number, because the mean of its divisors is an integer number (5906994).

Almost surely, 2^11813987 is an apocalyptic number.

11813987 is a deficient number, since it is larger than the sum of its proper divisors (1).

11813987 is an equidigital number, since it uses as much as digits as its factorization.

11813987 is an evil number, because the sum of its binary digits is even.

The product of its digits is 12096, while the sum is 38.

The square root of 11813987 is about 3437.1480910778. The cubic root of 11813987 is about 227.7537289083.

The spelling of 11813987 in words is "eleven million, eight hundred thirteen thousand, nine hundred eighty-seven".