72511781033 has 2 divisors, whose sum is σ = 72511781034. Its totient is φ = 72511781032.

The previous prime is 72511781021. The next prime is 72511781077. The reversal of 72511781033 is 33018711527.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 37905364249 + 34606416784 = 194693^2 + 186028^2 .

It is an emirp because it is prime and its reverse (33018711527) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 72511781033 - 2¹⁴ = 72511764649 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (72511781003) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 36255890516 + 36255890517.

It is an arithmetic number, because the mean of its divisors is an integer number (36255890517).

Almost surely, 2^72511781033 is an apocalyptic number.

It is an amenable number.

72511781033 is a deficient number, since it is larger than the sum of its proper divisors (1).

72511781033 is an equidigital number, since it uses as much as digits as its factorization.

72511781033 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 35280, while the sum is 38.

The spelling of 72511781033 in words is "seventy-two billion, five hundred eleven million, seven hundred eighty-one thousand, thirty-three".