221572830 has 16 divisors (see below), whose sum is σ = 531774864. Its totient is φ = 59086080.

The previous prime is 221572829. The next prime is 221572831. The reversal of 221572830 is 38275122.

It is an interprime number because it is at equal distance from previous prime (221572829) and next prime (221572831).

It is a Harshad number since it is a multiple of its sum of digits (30), and also a Moran number because the ratio is a prime number: 7385761 = 221572830 / (2 + 2 + 1 + 5 + 7 + 2 + 8 + 3 + 0).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (221572831) 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, 3692851 + ... + 3692910.

It is an arithmetic number, because the mean of its divisors is an integer number (33235929).

Almost surely, 2^221572830 is an apocalyptic number.

221572830 is an abundant number, since it is smaller than the sum of its proper divisors (310202034).

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

221572830 is a wasteful number, since it uses less digits than its factorization.

221572830 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7385771.

The product of its (nonzero) digits is 6720, while the sum is 30.

The square root of 221572830 is about 14885.3226367452. The cubic root of 221572830 is about 605.1162766288.

The spelling of 221572830 in words is "two hundred twenty-one million, five hundred seventy-two thousand, eight hundred thirty".