73287028721 has 4 divisors (see below), whose sum is σ = 73385666112. Its totient is φ = 73188391332.

The previous prime is 73287028693. The next prime is 73287028733. The reversal of 73287028721 is 12782078237.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 12782078237 = 2447 ⋅5223571.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-73287028721 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (73287048721) 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 3 ways as a sum of consecutive naturals, for example, 49317581 + ... + 49319066.

It is an arithmetic number, because the mean of its divisors is an integer number (18346416528).

Almost surely, 2^73287028721 is an apocalyptic number.

It is an amenable number.

73287028721 is a deficient number, since it is larger than the sum of its proper divisors (98637391).

73287028721 is an equidigital number, since it uses as much as digits as its factorization.

73287028721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 98637390.

The product of its (nonzero) digits is 526848, while the sum is 47.

The spelling of 73287028721 in words is "seventy-three billion, two hundred eighty-seven million, twenty-eight thousand, seven hundred twenty-one".