11781231 has 16 divisors (see below), whose sum is σ = 19584768. Its totient is φ = 6120000.

The previous prime is 11781199. The next prime is 11781233. The reversal of 11781231 is 13218711.

It is a happy number.

It is not a de Polignac number, because 11781231 - 2⁵ = 11781199 is a prime.

It is a super-2 number, since 2×11781231² = 277594807750722, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (11781233) 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, 25270 + ... + 25731.

It is an arithmetic number, because the mean of its divisors is an integer number (1224048).

Almost surely, 2^11781231 is an apocalyptic number.

11781231 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

11781231 is a deficient number, since it is larger than the sum of its proper divisors (7803537).

11781231 is a wasteful number, since it uses less digits than its factorization.

11781231 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 51022.

The product of its digits is 336, while the sum is 24.

The square root of 11781231 is about 3432.3797866786. The cubic root of 11781231 is about 227.5430406028.

Adding to 11781231 its reverse (13218711), we get a palindrome (24999942).

The spelling of 11781231 in words is "eleven million, seven hundred eighty-one thousand, two hundred thirty-one".