72473850721 has 2 divisors, whose sum is σ = 72473850722. Its totient is φ = 72473850720.

The previous prime is 72473850707. The next prime is 72473850739. The reversal of 72473850721 is 12705837427.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 71965573696 + 508277025 = 268264^2 + 22545^2 .

It is an emirp because it is prime and its reverse (12705837427) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 72473850721 - 2¹⁵ = 72473817953 is a prime.

It is not a weakly prime, because it can be changed into another prime (72473851721) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 36236925360 + 36236925361.

It is an arithmetic number, because the mean of its divisors is an integer number (36236925361).

Almost surely, 2^72473850721 is an apocalyptic number.

It is an amenable number.

72473850721 is a deficient number, since it is larger than the sum of its proper divisors (1).

72473850721 is an equidigital number, since it uses as much as digits as its factorization.

72473850721 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 658560, while the sum is 46.

The spelling of 72473850721 in words is "seventy-two billion, four hundred seventy-three million, eight hundred fifty thousand, seven hundred twenty-one".