72306656721346 has 16 divisors (see below), whose sum is σ = 108751219106040. Its totient is φ = 36056379191040.

The previous prime is 72306656721337. The next prime is 72306656721347. The reversal of 72306656721346 is 64312765660327.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 69014373485121 + 3292283236225 = 8307489^2 + 1814465^2 .

It is not an unprimeable number, because it can be changed into a prime (72306656721347) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 31086375 + ... + 33331306.

Almost surely, 2^{72306656721346} is an apocalyptic number.

72306656721346 is a deficient number, since it is larger than the sum of its proper divisors (36444562384694).

72306656721346 is a wasteful number, since it uses less digits than its factorization.

72306656721346 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 64419189.

The product of its (nonzero) digits is 45722880, while the sum is 58.

The spelling of 72306656721346 in words is "seventy-two trillion, three hundred six billion, six hundred fifty-six million, seven hundred twenty-one thousand, three hundred forty-six".