72120555050021 has 2 divisors, whose sum is σ = 72120555050022. Its totient is φ = 72120555050020.

The previous prime is 72120555049981. The next prime is 72120555050051. The reversal of 72120555050021 is 12005055502127.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 46136507572996 + 25984047477025 = 6792386^2 + 5097455^2 .

It is a cyclic number.

It is not a de Polignac number, because 72120555050021 - 2²⁶ = 72120487941157 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (72120555050051) 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, 36060277525010 + 36060277525011.

It is an arithmetic number, because the mean of its divisors is an integer number (36060277525011).

Almost surely, 2^{72120555050021} is an apocalyptic number.

It is an amenable number.

72120555050021 is a deficient number, since it is larger than the sum of its proper divisors (1).

72120555050021 is an equidigital number, since it uses as much as digits as its factorization.

72120555050021 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 35000, while the sum is 35.

The spelling of 72120555050021 in words is "seventy-two trillion, one hundred twenty billion, five hundred fifty-five million, fifty thousand, twenty-one".