721677125173 has 2 divisors, whose sum is σ = 721677125174. Its totient is φ = 721677125172.

The previous prime is 721677125087. The next prime is 721677125177. The reversal of 721677125173 is 371521776127.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 656913492004 + 64763633169 = 810502^2 + 254487^2 .

It is a cyclic number.

It is not a de Polignac number, because 721677125173 - 2²¹ = 721675028021 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (721677125177) 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, 360838562586 + 360838562587.

It is an arithmetic number, because the mean of its divisors is an integer number (360838562587).

Almost surely, 2^721677125173 is an apocalyptic number.

It is an amenable number.

721677125173 is a deficient number, since it is larger than the sum of its proper divisors (1).

721677125173 is an equidigital number, since it uses as much as digits as its factorization.

721677125173 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 864360, while the sum is 49.

The spelling of 721677125173 in words is "seven hundred twenty-one billion, six hundred seventy-seven million, one hundred twenty-five thousand, one hundred seventy-three".