721665056670073 has 16 divisors (see below), whose sum is σ = 754215556939776. Its totient is φ = 689212427273920.

The previous prime is 721665056670029. The next prime is 721665056670121. The reversal of 721665056670073 is 370076650566127.

It is a cyclic number.

It is not a de Polignac number, because 721665056670073 - 2⁴¹ = 719466033414521 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 721665056669993 and 721665056670020.

It is not an unprimeable number, because it can be changed into a prime (721665056670473) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 566796936 + ... + 568068742.

It is an arithmetic number, because the mean of its divisors is an integer number (47138472308736).

Almost surely, 2^{721665056670073} is an apocalyptic number.

It is an amenable number.

721665056670073 is a deficient number, since it is larger than the sum of its proper divisors (32550500269703).

721665056670073 is a wasteful number, since it uses less digits than its factorization.

721665056670073 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1310264.

The product of its (nonzero) digits is 66679200, while the sum is 61.

The spelling of 721665056670073 in words is "seven hundred twenty-one trillion, six hundred sixty-five billion, fifty-six million, six hundred seventy thousand, seventy-three".