221055507 has 16 divisors (see below), whose sum is σ = 341729280. Its totient is φ = 140962536.

The previous prime is 221055491. The next prime is 221055511. The reversal of 221055507 is 705550122.

It is a happy number.

221055507 is a `hidden beast` number, since 2 + 2 + 105 + 550 + 7 = 666.

It is not a de Polignac number, because 221055507 - 2⁴ = 221055491 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is not an unprimeable number, because it can be changed into a prime (221055517) 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, 177363 + ... + 178604.

It is an arithmetic number, because the mean of its divisors is an integer number (21358080).

Almost surely, 2^221055507 is an apocalyptic number.

221055507 is a gapful number since it is divisible by the number (27) formed by its first and last digit.

221055507 is a deficient number, since it is larger than the sum of its proper divisors (120673773).

221055507 is a wasteful number, since it uses less digits than its factorization.

221055507 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 355999 (or 355993 counting only the distinct ones).

The product of its (nonzero) digits is 3500, while the sum is 27.

The square root of 221055507 is about 14867.9355325479. The cubic root of 221055507 is about 604.6449725875.

The spelling of 221055507 in words is "two hundred twenty-one million, fifty-five thousand, five hundred seven".