221270100 has 36 divisors (see below), whose sum is σ = 640209024. Its totient is φ = 59005280.

The previous prime is 221270089. The next prime is 221270107. The reversal of 221270100 is 1072122.

It is a Harshad number since it is a multiple of its sum of digits (15).

It is a self number, because there is not a number n which added to its sum of digits gives 221270100.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (221270107) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 368484 + ... + 369083.

It is an arithmetic number, because the mean of its divisors is an integer number (17783584).

Almost surely, 2^221270100 is an apocalyptic number.

221270100 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

221270100 is an abundant number, since it is smaller than the sum of its proper divisors (418938924).

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

221270100 is a wasteful number, since it uses less digits than its factorization.

221270100 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 737584 (or 737577 counting only the distinct ones).

The product of its (nonzero) digits is 56, while the sum is 15.

The square root of 221270100 is about 14875.1504194075. The cubic root of 221270100 is about 604.8405654148.

The spelling of 221270100 in words is "two hundred twenty-one million, two hundred seventy thousand, one hundred".