721690367 has 2 divisors, whose sum is σ = 721690368. Its totient is φ = 721690366.

The previous prime is 721690339. The next prime is 721690369. The reversal of 721690367 is 763096127.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 721690367 - 2¹⁰ = 721689343 is a prime.

Together with 721690369, it forms a pair of twin primes.

It is a Chen prime.

It is an alternating number because its digits alternate between odd and even.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (721690369) 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 as a sum of consecutive naturals, namely, 360845183 + 360845184.

It is an arithmetic number, because the mean of its divisors is an integer number (360845184).

Almost surely, 2^721690367 is an apocalyptic number.

721690367 is a deficient number, since it is larger than the sum of its proper divisors (1).

721690367 is an equidigital number, since it uses as much as digits as its factorization.

721690367 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 95256, while the sum is 41.

The square root of 721690367 is about 26864.2953937005. The cubic root of 721690367 is about 896.9818102580.

The spelling of 721690367 in words is "seven hundred twenty-one million, six hundred ninety thousand, three hundred sixty-seven".