821642277673 has 32 divisors (see below), whose sum is σ = 964612712448. Its totient is φ = 685168848000.

The previous prime is 821642277629. The next prime is 821642277707. The reversal of 821642277673 is 376772246128.

It is not a de Polignac number, because 821642277673 - 2²¹ = 821640180521 is a prime.

It is a Smith number, since the sum of its digits (55) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is not an unprimeable number, because it can be changed into a prime (821642277173) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 227789236 + ... + 227792842.

It is an arithmetic number, because the mean of its divisors is an integer number (30144147264).

Almost surely, 2^821642277673 is an apocalyptic number.

It is an amenable number.

821642277673 is a deficient number, since it is larger than the sum of its proper divisors (142970434775).

821642277673 is a wasteful number, since it uses less digits than its factorization.

821642277673 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5653.

The product of its digits is 9483264, while the sum is 55.

The spelling of 821642277673 in words is "eight hundred twenty-one billion, six hundred forty-two million, two hundred seventy-seven thousand, six hundred seventy-three".