221512571172772 has 24 divisors (see below), whose sum is σ = 425929992979680. Its totient is φ = 99963161612160.

The previous prime is 221512571172731. The next prime is 221512571172773. The reversal of 221512571172772 is 277271175215122.

It is not an unprimeable number, because it can be changed into a prime (221512571172773) 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, 18109262293 + ... + 18109274524.

It is an arithmetic number, because the mean of its divisors is an integer number (17747083040820).

Almost surely, 2^{221512571172772} is an apocalyptic number.

221512571172772 is a gapful number since it is divisible by the number (22) formed by its first and last digit.

It is an amenable number.

221512571172772 is a deficient number, since it is larger than the sum of its proper divisors (204417421806908).

221512571172772 is a wasteful number, since it uses less digits than its factorization.

221512571172772 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 36218536971 (or 36218536969 counting only the distinct ones).

The product of its digits is 1920800, while the sum is 52.

The spelling of 221512571172772 in words is "two hundred twenty-one trillion, five hundred twelve billion, five hundred seventy-one million, one hundred seventy-two thousand, seven hundred seventy-two".