221662566451 has 4 divisors (see below), whose sum is σ = 222811077352. Its totient is φ = 220514055552.

The previous prime is 221662566383. The next prime is 221662566469. The reversal of 221662566451 is 154665266122.

221662566451 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-221662566451 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (221662560451) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 574255161 + ... + 574255546.

It is an arithmetic number, because the mean of its divisors is an integer number (55702769338).

Almost surely, 2^221662566451 is an apocalyptic number.

221662566451 is a deficient number, since it is larger than the sum of its proper divisors (1148510901).

221662566451 is a wasteful number, since it uses less digits than its factorization.

221662566451 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1148510900.

The product of its digits is 1036800, while the sum is 46.

The spelling of 221662566451 in words is "two hundred twenty-one billion, six hundred sixty-two million, five hundred sixty-six thousand, four hundred fifty-one".