11802981981 has 16 divisors (see below), whose sum is σ = 18471592064. Its totient is φ = 6562275264.

The previous prime is 11802981977. The next prime is 11802982007. The reversal of 11802981981 is 18918920811.

It is a happy number.

It is not a de Polignac number, because 11802981981 - 2² = 11802981977 is a prime.

It is a super-2 number, since 2×11802981981² (a number of 21 digits) contains 22 as substring.

It is a Smith number, since the sum of its digits (48) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 11802981981.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (11802981781) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 7594450 + ... + 7596003.

It is an arithmetic number, because the mean of its divisors is an integer number (1154474504).

Almost surely, 2^11802981981 is an apocalyptic number.

It is an amenable number.

11802981981 is a deficient number, since it is larger than the sum of its proper divisors (6668610083).

11802981981 is a wasteful number, since it uses less digits than its factorization.

11802981981 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15190500.

The product of its (nonzero) digits is 82944, while the sum is 48.

The spelling of 11802981981 in words is "eleven billion, eight hundred two million, nine hundred eighty-one thousand, nine hundred eighty-one".