721137818579 has 2 divisors, whose sum is σ = 721137818580. Its totient is φ = 721137818578.

The previous prime is 721137818537. The next prime is 721137818617. The reversal of 721137818579 is 975818731127.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 721137818579 - 2¹⁶ = 721137753043 is a prime.

It is not a weakly prime, because it can be changed into another prime (721137815579) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 360568909289 + 360568909290.

It is an arithmetic number, because the mean of its divisors is an integer number (360568909290).

Almost surely, 2^721137818579 is an apocalyptic number.

721137818579 is a deficient number, since it is larger than the sum of its proper divisors (1).

721137818579 is an equidigital number, since it uses as much as digits as its factorization.

721137818579 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 5927040, while the sum is 59.

The spelling of 721137818579 in words is "seven hundred twenty-one billion, one hundred thirty-seven million, eight hundred eighteen thousand, five hundred seventy-nine".