221645430 has 32 divisors (see below), whose sum is σ = 591055200. Its totient is φ = 59105376.

The previous prime is 221645423. The next prime is 221645461. The reversal of 221645430 is 34546122.

221645430 is a `hidden beast` number, since 221 + 6 + 4 + 5 + 430 = 666.

221645430 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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

It is a junction number, because it is equal to n+sod(n) for n = 221645394 and 221645403.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 410185 + ... + 410724.

It is an arithmetic number, because the mean of its divisors is an integer number (18470475).

Almost surely, 2^221645430 is an apocalyptic number.

221645430 is an abundant number, since it is smaller than the sum of its proper divisors (369409770).

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

221645430 is a wasteful number, since it uses less digits than its factorization.

221645430 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 820925 (or 820919 counting only the distinct ones).

The product of its (nonzero) digits is 5760, while the sum is 27.

The square root of 221645430 is about 14887.7610808341. The cubic root of 221645430 is about 605.1823597077.

The spelling of 221645430 in words is "two hundred twenty-one million, six hundred forty-five thousand, four hundred thirty".