12261455550 has 72 divisors (see below), whose sum is σ = 33268730040. Its totient is φ = 3237336000.

The previous prime is 12261455509. The next prime is 12261455561. The reversal of 12261455550 is 5555416221.

12261455550 is a `hidden beast` number, since 1 + 2 + 2 + 61 + 45 + 5 + 550 = 666.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 89440 + ... + 180339.

It is an arithmetic number, because the mean of its divisors is an integer number (462065695).

Almost surely, 2^12261455550 is an apocalyptic number.

12261455550 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

12261455550 is an abundant number, since it is smaller than the sum of its proper divisors (21007274490).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

12261455550 is a wasteful number, since it uses less digits than its factorization.

12261455550 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 269898 (or 269890 counting only the distinct ones).

The product of its (nonzero) digits is 60000, while the sum is 36.

The spelling of 12261455550 in words is "twelve billion, two hundred sixty-one million, four hundred fifty-five thousand, five hundred fifty".