721066979 has 2 divisors, whose sum is σ = 721066980. Its totient is φ = 721066978.

The previous prime is 721066949. The next prime is 721066987. The reversal of 721066979 is 979660127.

It is a strong prime.

It is an emirp because it is prime and its reverse (979660127) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 721066979 - 2²⁸ = 452631523 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (721066919) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 360533489 + 360533490.

It is an arithmetic number, because the mean of its divisors is an integer number (360533490).

Almost surely, 2^721066979 is an apocalyptic number.

721066979 is a deficient number, since it is larger than the sum of its proper divisors (1).

721066979 is an equidigital number, since it uses as much as digits as its factorization.

721066979 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 285768, while the sum is 47.

The square root of 721066979 is about 26852.6903493859. The cubic root of 721066979 is about 896.7234682688.

The spelling of 721066979 in words is "seven hundred twenty-one million, sixty-six thousand, nine hundred seventy-nine".