11123981 has 4 divisors (see below), whose sum is σ = 12135264. Its totient is φ = 10112700.

The previous prime is 11123963. The next prime is 11124053. The reversal of 11123981 is 18932111.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 11123981 - 2²² = 6929677 is a prime.

It is a super-2 number, since 2×11123981² = 247485906576722, which contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 11123981.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (11120981) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 505625 + ... + 505646.

It is an arithmetic number, because the mean of its divisors is an integer number (3033816).

Almost surely, 2^11123981 is an apocalyptic number.

11123981 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

11123981 is a deficient number, since it is larger than the sum of its proper divisors (1011283).

11123981 is a wasteful number, since it uses less digits than its factorization.

11123981 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1011282.

The product of its digits is 432, while the sum is 26.

The square root of 11123981 is about 3335.2632579753. The cubic root of 11123981 is about 223.2304387280.

The spelling of 11123981 in words is "eleven million, one hundred twenty-three thousand, nine hundred eighty-one".