806445499621 has 4 divisors (see below), whose sum is σ = 815506685100. Its totient is φ = 797384314144.

The previous prime is 806445499591. The next prime is 806445499709. The reversal of 806445499621 is 126994544608.

It is a happy number.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 149436364900 + 657009134721 = 386570^2 + 810561^2 .

It is a cyclic number.

It is not a de Polignac number, because 806445499621 - 2⁷ = 806445499493 is a prime.

It is a super-2 number, since 2×806445499621² (a number of 25 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (806445499721) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4530592606 + ... + 4530592783.

It is an arithmetic number, because the mean of its divisors is an integer number (203876671275).

Almost surely, 2^806445499621 is an apocalyptic number.

It is an amenable number.

806445499621 is a deficient number, since it is larger than the sum of its proper divisors (9061185479).

806445499621 is an equidigital number, since it uses as much as digits as its factorization.

806445499621 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9061185478.

The product of its (nonzero) digits is 14929920, while the sum is 58.

The spelling of 806445499621 in words is "eight hundred six billion, four hundred forty-five million, four hundred ninety-nine thousand, six hundred twenty-one".