221666054 has 16 divisors (see below), whose sum is σ = 336296448. Its totient is φ = 109573632.

The previous prime is 221666051. The next prime is 221666057. The reversal of 221666054 is 450666122.

221666054 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is an interprime number because it is at equal distance from previous prime (221666051) and next prime (221666057).

It is a self number, because there is not a number n which added to its sum of digits gives 221666054.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (221666051) 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, 79142 + ... + 81894.

It is an arithmetic number, because the mean of its divisors is an integer number (21018528).

Almost surely, 2^221666054 is an apocalyptic number.

221666054 is a deficient number, since it is larger than the sum of its proper divisors (114630394).

221666054 is a wasteful number, since it uses less digits than its factorization.

221666054 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3199.

The product of its (nonzero) digits is 17280, while the sum is 32.

The square root of 221666054 is about 14888.4537142042. The cubic root of 221666054 is about 605.2011297674.

The spelling of 221666054 in words is "two hundred twenty-one million, six hundred sixty-six thousand, fifty-four".