221393407 has 8 divisors (see below), whose sum is σ = 225054720. Its totient is φ = 217747320.

The previous prime is 221393401. The next prime is 221393441. The reversal of 221393407 is 704393122.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 221393407 - 2¹⁹ = 220869119 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 (221393401) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 27618 + ... + 34720.

It is an arithmetic number, because the mean of its divisors is an integer number (28131840).

Almost surely, 2^221393407 is an apocalyptic number.

221393407 is a deficient number, since it is larger than the sum of its proper divisors (3661313).

221393407 is an equidigital number, since it uses as much as digits as its factorization.

221393407 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7613.

The product of its (nonzero) digits is 9072, while the sum is 31.

The square root of 221393407 is about 14879.2945733324. The cubic root of 221393407 is about 604.9528975464.

The spelling of 221393407 in words is "two hundred twenty-one million, three hundred ninety-three thousand, four hundred seven".