264223721 has 4 divisors (see below), whose sum is σ = 270668244. Its totient is φ = 257779200.

The previous prime is 264223681. The next prime is 264223723. The reversal of 264223721 is 127322462.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 127322462 = 2 ⋅63661231.

It can be written as a sum of positive squares in 2 ways, for example, as 115261696 + 148962025 = 10736^2 + 12205^2 .

It is a cyclic number.

It is not a de Polignac number, because 264223721 - 2²² = 260029417 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (264223723) 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, 3222200 + ... + 3222281.

It is an arithmetic number, because the mean of its divisors is an integer number (67667061).

Almost surely, 2^264223721 is an apocalyptic number.

It is an amenable number.

264223721 is a deficient number, since it is larger than the sum of its proper divisors (6444523).

264223721 is an equidigital number, since it uses as much as digits as its factorization.

264223721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6444522.

The product of its digits is 8064, while the sum is 29.

The square root of 264223721 is about 16254.9598892154. The cubic root of 264223721 is about 641.6880251356.

The spelling of 264223721 in words is "two hundred sixty-four million, two hundred twenty-three thousand, seven hundred twenty-one".