72462717721 has 3 divisors (see below), whose sum is σ = 72462986911. Its totient is φ = 72462448532.

The previous prime is 72462717667. The next prime is 72462717749. The reversal of 72462717721 is 12771726427.

It is a happy number.

The square root of 72462717721 is 269189.

It is a perfect power (a square), and thus also a powerful number.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It can be written as a sum of positive squares in only one way, i.e., 585107721 + 71877610000 = 24189^2 + 268100^2 .

It is not a de Polignac number, because 72462717721 - 2¹⁵ = 72462684953 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (72462717421) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 2 ways as a sum of consecutive naturals, for example, 134595 + ... + 403783.

Almost surely, 2^72462717721 is an apocalyptic number.

72462717721 is the 269189-th square number.

72462717721 is the 134595-th centered octagonal number.

It is an amenable number.

72462717721 is a deficient number, since it is larger than the sum of its proper divisors (269190).

72462717721 is an frugal number, since it uses more digits than its factorization.

72462717721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 538378 (or 269189 counting only the distinct ones).

The product of its digits is 460992, while the sum is 46.

The spelling of 72462717721 in words is "seventy-two billion, four hundred sixty-two million, seven hundred seventeen thousand, seven hundred twenty-one".