72781636387888 has 10 divisors (see below), whose sum is σ = 141014420501564. Its totient is φ = 36390818193936.

The previous prime is 72781636387877. The next prime is 72781636387969. The reversal of 72781636387888 is 88878363618727.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2274426137106 + ... + 2274426137137.

Almost surely, 2^{72781636387888} is an apocalyptic number.

It is an amenable number.

72781636387888 is a deficient number, since it is larger than the sum of its proper divisors (68232784113676).

72781636387888 is a wasteful number, since it uses less digits than its factorization.

72781636387888 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4548852274251 (or 4548852274245 counting only the distinct ones).

The product of its digits is 7283146752, while the sum is 82.

The spelling of 72781636387888 in words is "seventy-two trillion, seven hundred eighty-one billion, six hundred thirty-six million, three hundred eighty-seven thousand, eight hundred eighty-eight".