11007981 has 20 divisors (see below), whose sum is σ = 16893052. Its totient is φ = 7138368.

The previous prime is 11007977. The next prime is 11007989. The reversal of 11007981 is 18970011.

It can be written as a sum of positive squares in 2 ways, for example, as 5103081 + 5904900 = 2259^2 + 2430^2 .

It is not a de Polignac number, because 11007981 - 2² = 11007977 is a prime.

It is a super-2 number, since 2×11007981² = 242351291392722, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (11007989) by changing a digit.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 1161 + ... + 4833.

Almost surely, 2^11007981 is an apocalyptic number.

It is an amenable number.

11007981 is a deficient number, since it is larger than the sum of its proper divisors (5885071).

11007981 is an equidigital number, since it uses as much as digits as its factorization.

11007981 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3722 (or 3713 counting only the distinct ones).

The product of its (nonzero) digits is 504, while the sum is 27.

The square root of 11007981 is about 3317.8277532144. The cubic root of 11007981 is about 222.4517826755.

Adding to 11007981 its reverse (18970011), we get a palindrome (29977992).

The spelling of 11007981 in words is "eleven million, seven thousand, nine hundred eighty-one".