72821978271 has 96 divisors (see below), whose sum is σ = 127281623040. Its totient is φ = 39237343488.

The previous prime is 72821978269. The next prime is 72821978377. The reversal of 72821978271 is 17287912827.

72821978271 is a `hidden beast` number, since 7 + 282 + 1 + 97 + 8 + 271 = 666.

It is not a de Polignac number, because 72821978271 - 2¹ = 72821978269 is a prime.

It is a super-2 number, since 2×72821978271² (a number of 23 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (72821978261) 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 95 ways as a sum of consecutive naturals, for example, 75306630 + ... + 75307596.

It is an arithmetic number, because the mean of its divisors is an integer number (1325850240).

Almost surely, 2^72821978271 is an apocalyptic number.

72821978271 is a deficient number, since it is larger than the sum of its proper divisors (54459644769).

72821978271 is a wasteful number, since it uses less digits than its factorization.

72821978271 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1933 (or 1930 counting only the distinct ones).

The product of its digits is 1580544, while the sum is 54.

The spelling of 72821978271 in words is "seventy-two billion, eight hundred twenty-one million, nine hundred seventy-eight thousand, two hundred seventy-one".