71780665252 has 12 divisors (see below), whose sum is σ = 125622495180. Its totient is φ = 35888523776.

The previous prime is 71780665249. The next prime is 71780665283. The reversal of 71780665252 is 25256608717.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 59391639616 + 12389025636 = 243704^2 + 111306^2 .

It is a junction number, because it is equal to n+sod(n) for n = 71780665196 and 71780665205.

It is an unprimeable number.

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 in 3 ways as a sum of consecutive naturals, for example, 360877 + ... + 523252.

It is an arithmetic number, because the mean of its divisors is an integer number (10468541265).

Almost surely, 2^71780665252 is an apocalyptic number.

It is an amenable number.

71780665252 is a deficient number, since it is larger than the sum of its proper divisors (53841829928).

71780665252 is a wasteful number, since it uses less digits than its factorization.

71780665252 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 904430 (or 904428 counting only the distinct ones).

The product of its (nonzero) digits is 1411200, while the sum is 49.

The spelling of 71780665252 in words is "seventy-one billion, seven hundred eighty million, six hundred sixty-five thousand, two hundred fifty-two".