221431005 has 24 divisors (see below), whose sum is σ = 400503168. Its totient is φ = 112961376.

The previous prime is 221430983. The next prime is 221431019. The reversal of 221431005 is 500134122.

It is not a de Polignac number, because 221431005 - 2²⁷ = 87213277 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 105937 + ... + 108006.

It is an arithmetic number, because the mean of its divisors is an integer number (16687632).

Almost surely, 2^221431005 is an apocalyptic number.

It is an amenable number.

221431005 is a deficient number, since it is larger than the sum of its proper divisors (179072163).

221431005 is a wasteful number, since it uses less digits than its factorization.

221431005 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 213977 (or 213974 counting only the distinct ones).

The product of its (nonzero) digits is 240, while the sum is 18.

The square root of 221431005 is about 14880.5579532489. The cubic root of 221431005 is about 604.9871408600.

Adding to 221431005 its reverse (500134122), we get a palindrome (721565127).

The spelling of 221431005 in words is "two hundred twenty-one million, four hundred thirty-one thousand, five".