221933421 has 6 divisors (see below), whose sum is σ = 320570510. Its totient is φ = 147955608.

The previous prime is 221933401. The next prime is 221933423. The reversal of 221933421 is 124339122.

It is a happy number.

It can be written as a sum of positive squares in only one way, i.e., 201952521 + 19980900 = 14211^2 + 4470^2 .

It is not a de Polignac number, because 221933421 - 2¹⁰ = 221932397 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (221933423) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 12329626 + ... + 12329643.

Almost surely, 2^221933421 is an apocalyptic number.

It is an amenable number.

221933421 is a deficient number, since it is larger than the sum of its proper divisors (98637089).

221933421 is a wasteful number, since it uses less digits than its factorization.

221933421 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 24659275 (or 24659272 counting only the distinct ones).

The product of its digits is 2592, while the sum is 27.

The square root of 221933421 is about 14897.4300132607. The cubic root of 221933421 is about 605.4443572019. Note that the first 3 decimals are identical.

The spelling of 221933421 in words is "two hundred twenty-one million, nine hundred thirty-three thousand, four hundred twenty-one".