221404051 has 4 divisors (see below), whose sum is σ = 241531704. Its totient is φ = 201276400.

The previous prime is 221404037. The next prime is 221404061. The reversal of 221404051 is 150404122.

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

It is a cyclic number.

It is not a de Polignac number, because 221404051 - 2¹⁷ = 221272979 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (221404021) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 10063810 + ... + 10063831.

It is an arithmetic number, because the mean of its divisors is an integer number (60382926).

Almost surely, 2^221404051 is an apocalyptic number.

221404051 is a deficient number, since it is larger than the sum of its proper divisors (20127653).

221404051 is a wasteful number, since it uses less digits than its factorization.

221404051 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 20127652.

The product of its (nonzero) digits is 320, while the sum is 19.

The square root of 221404051 is about 14879.6522472805. The cubic root of 221404051 is about 604.9625922275.

Adding to 221404051 its reverse (150404122), we get a palindrome (371808173).

The spelling of 221404051 in words is "two hundred twenty-one million, four hundred four thousand, fifty-one".