221456906 has 16 divisors (see below), whose sum is σ = 363575520. Its totient is φ = 100331280.

The previous prime is 221456899. The next prime is 221456927. The reversal of 221456906 is 609654122.

It is a happy number.

It is a super-2 number, since 2×221456906² = 98086322430185672, which contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 9641 + ... + 23148.

It is an arithmetic number, because the mean of its divisors is an integer number (22723470).

Almost surely, 2^221456906 is an apocalyptic number.

221456906 is a deficient number, since it is larger than the sum of its proper divisors (142118614).

221456906 is a wasteful number, since it uses less digits than its factorization.

221456906 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 33109.

The product of its (nonzero) digits is 25920, while the sum is 35.

The square root of 221456906 is about 14881.4282244682. The cubic root of 221456906 is about 605.0107285851.

The spelling of 221456906 in words is "two hundred twenty-one million, four hundred fifty-six thousand, nine hundred six".