221606072 has 8 divisors (see below), whose sum is σ = 415511400. Its totient is φ = 110803032.

The previous prime is 221606069. The next prime is 221606089. The reversal of 221606072 is 270606122.

221606072 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a tau number, because it is divible by the number of its divisors (8).

It is a super-2 number, since 2×221606072² = 98218502294538368, which contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 13850372 + ... + 13850387.

It is an arithmetic number, because the mean of its divisors is an integer number (51938925).

Almost surely, 2^221606072 is an apocalyptic number.

It is an amenable number.

221606072 is a deficient number, since it is larger than the sum of its proper divisors (193905328).

221606072 is a wasteful number, since it uses less digits than its factorization.

221606072 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 27700765 (or 27700761 counting only the distinct ones).

The product of its (nonzero) digits is 2016, while the sum is 26.

The square root of 221606072 is about 14886.4391981427. The cubic root of 221606072 is about 605.1465364601.

Subtracting 221606072 from its reverse (270606122), we obtain a triangular number (49000050 = T₉₈₉₉).

The spelling of 221606072 in words is "two hundred twenty-one million, six hundred six thousand, seventy-two".