721644314 has 4 divisors (see below), whose sum is σ = 1082466474. Its totient is φ = 360822156.

The previous prime is 721644311. The next prime is 721644317. The reversal of 721644314 is 413446127.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 413446127 = 29 ⋅14256763.

It is an interprime number because it is at equal distance from previous prime (721644311) and next prime (721644317).

It can be written as a sum of positive squares in only one way, i.e., 701349289 + 20295025 = 26483^2 + 4505^2 .

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (721644311) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 180411077 + ... + 180411080.

Almost surely, 2^721644314 is an apocalyptic number.

721644314 is a deficient number, since it is larger than the sum of its proper divisors (360822160).

721644314 is a wasteful number, since it uses less digits than its factorization.

721644314 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 360822159.

The product of its digits is 16128, while the sum is 32.

The square root of 721644314 is about 26863.4382386172. The cubic root of 721644314 is about 896.9627302463.

The spelling of 721644314 in words is "seven hundred twenty-one million, six hundred forty-four thousand, three hundred fourteen".