445756721566421 has 16 divisors (see below), whose sum is σ = 477495306284544. Its totient is φ = 415141966930944.

The previous prime is 445756721566357. The next prime is 445756721566441. The reversal of 445756721566421 is 124665127657544.

It is not a de Polignac number, because 445756721566421 - 2⁶ = 445756721566357 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (445756721566441) 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, 1068070886 + ... + 1068488151.

It is an arithmetic number, because the mean of its divisors is an integer number (29843456642784).

Almost surely, 2^{445756721566421} is an apocalyptic number.

It is an amenable number.

445756721566421 is a deficient number, since it is larger than the sum of its proper divisors (31738584718123).

445756721566421 is a wasteful number, since it uses less digits than its factorization.

445756721566421 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2136559300.

The product of its digits is 338688000, while the sum is 65.

The spelling of 445756721566421 in words is "four hundred forty-five trillion, seven hundred fifty-six billion, seven hundred twenty-one million, five hundred sixty-six thousand, four hundred twenty-one".