721323143 has 2 divisors, whose sum is σ = 721323144. Its totient is φ = 721323142.

The previous prime is 721323121. The next prime is 721323149. The reversal of 721323143 is 341323127.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 721323143 - 2¹² = 721319047 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (721323149) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 360661571 + 360661572.

It is an arithmetic number, because the mean of its divisors is an integer number (360661572).

Almost surely, 2^721323143 is an apocalyptic number.

721323143 is a deficient number, since it is larger than the sum of its proper divisors (1).

721323143 is an equidigital number, since it uses as much as digits as its factorization.

721323143 is an evil number, because the sum of its binary digits is even.

The product of its digits is 3024, while the sum is 26.

The square root of 721323143 is about 26857.4597272341. The cubic root of 721323143 is about 896.8296447549.

The spelling of 721323143 in words is "seven hundred twenty-one million, three hundred twenty-three thousand, one hundred forty-three".