11799981 has 6 divisors (see below), whose sum is σ = 17044430. Its totient is φ = 7866648.

The previous prime is 11799979. The next prime is 11800001. The reversal of 11799981 is 18999711.

11799981 is digitally balanced in base 2 and base 4, because in such bases it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in only one way, i.e., 6937956 + 4862025 = 2634^2 + 2205^2 .

It is not a de Polignac number, because 11799981 - 2¹ = 11799979 is a prime.

It is a super-2 number, since 2×11799981² = 278479103200722, which contains 22 as substring.

It is a Duffinian number.

It is a zygodrome in base 8.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (11799911) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 655546 + ... + 655563.

Almost surely, 2^11799981 is an apocalyptic number.

It is an amenable number.

11799981 is a deficient number, since it is larger than the sum of its proper divisors (5244449).

11799981 is a wasteful number, since it uses less digits than its factorization.

11799981 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1311115 (or 1311112 counting only the distinct ones).

The product of its digits is 40824, while the sum is 45.

The square root of 11799981 is about 3435.1100419055. The cubic root of 11799981 is about 227.6636893037.

The spelling of 11799981 in words is "eleven million, seven hundred ninety-nine thousand, nine hundred eighty-one".