131223555 has 24 divisors (see below), whose sum is σ = 228992400. Its totient is φ = 69512640.

The previous prime is 131223551. The next prime is 131223563. The reversal of 131223555 is 555322131.

It is a happy number.

It is not a de Polignac number, because 131223555 - 2² = 131223551 is a prime.

It is not an unprimeable number, because it can be changed into a prime (131223551) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 3081 + ... + 16490.

It is an arithmetic number, because the mean of its divisors is an integer number (9541350).

Almost surely, 2^131223555 is an apocalyptic number.

131223555 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

131223555 is a deficient number, since it is larger than the sum of its proper divisors (97768845).

131223555 is a wasteful number, since it uses less digits than its factorization.

131223555 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 19731 (or 19728 counting only the distinct ones).

The product of its digits is 4500, while the sum is 27.

The square root of 131223555 is about 11455.2850248259. The cubic root of 131223555 is about 508.1640445572.

Adding to 131223555 its reverse (555322131), we get a palindrome (686545686).

The spelling of 131223555 in words is "one hundred thirty-one million, two hundred twenty-three thousand, five hundred fifty-five".