12557667221 has 8 divisors (see below), whose sum is σ = 13722074688. Its totient is φ = 11397060000.

The previous prime is 12557667211. The next prime is 12557667293. The reversal of 12557667221 is 12276675521.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-12557667221 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12557667211) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 943145 + ... + 956366.

It is an arithmetic number, because the mean of its divisors is an integer number (1715259336).

Almost surely, 2^12557667221 is an apocalyptic number.

12557667221 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

12557667221 is a deficient number, since it is larger than the sum of its proper divisors (1164407467).

12557667221 is a wasteful number, since it uses less digits than its factorization.

12557667221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1900123.

The product of its digits is 352800, while the sum is 44.

The spelling of 12557667221 in words is "twelve billion, five hundred fifty-seven million, six hundred sixty-seven thousand, two hundred twenty-one".