721564367 has 2 divisors, whose sum is σ = 721564368. Its totient is φ = 721564366.

The previous prime is 721564357. The next prime is 721564369. The reversal of 721564367 is 763465127.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 721564367 - 2²⁴ = 704787151 is a prime.

It is a super-2 number, since 2×721564367² = 1041310271448221378, which contains 22 as substring.

Together with 721564369, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (721564369) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 360782183 + 360782184.

It is an arithmetic number, because the mean of its divisors is an integer number (360782184).

Almost surely, 2^721564367 is an apocalyptic number.

721564367 is a deficient number, since it is larger than the sum of its proper divisors (1).

721564367 is an equidigital number, since it uses as much as digits as its factorization.

721564367 is an evil number, because the sum of its binary digits is even.

The product of its digits is 211680, while the sum is 41.

The square root of 721564367 is about 26861.9501711994. The cubic root of 721564367 is about 896.9296058357.

The spelling of 721564367 in words is "seven hundred twenty-one million, five hundred sixty-four thousand, three hundred sixty-seven".