721848370121 has 2 divisors, whose sum is σ = 721848370122. Its totient is φ = 721848370120.

The previous prime is 721848370097. The next prime is 721848370129. The reversal of 721848370121 is 121073848127.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 395847338896 + 326001031225 = 629164^2 + 570965^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-721848370121 is a prime.

It is not a weakly prime, because it can be changed into another prime (721848370129) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 360924185060 + 360924185061.

It is an arithmetic number, because the mean of its divisors is an integer number (360924185061).

Almost surely, 2^721848370121 is an apocalyptic number.

It is an amenable number.

721848370121 is a deficient number, since it is larger than the sum of its proper divisors (1).

721848370121 is an equidigital number, since it uses as much as digits as its factorization.

721848370121 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 150528, while the sum is 44.

The spelling of 721848370121 in words is "seven hundred twenty-one billion, eight hundred forty-eight million, three hundred seventy thousand, one hundred twenty-one".