72221443643 has 4 divisors (see below), whose sum is σ = 72284191488. Its totient is φ = 72158695800.

The previous prime is 72221443639. The next prime is 72221443649. The reversal of 72221443643 is 34634412227.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 34634412227 = 739 ⋅46866593.

It is a cyclic number.

It is not a de Polignac number, because 72221443643 - 2² = 72221443639 is a prime.

It is a super-2 number, since 2×72221443643² (a number of 23 digits) contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 72221443597 and 72221443606.

It is not an unprimeable number, because it can be changed into a prime (72221443649) 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 3 ways as a sum of consecutive naturals, for example, 31372196 + ... + 31374497.

It is an arithmetic number, because the mean of its divisors is an integer number (18071047872).

Almost surely, 2^72221443643 is an apocalyptic number.

72221443643 is a deficient number, since it is larger than the sum of its proper divisors (62747845).

72221443643 is a wasteful number, since it uses less digits than its factorization.

72221443643 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 62747844.

The product of its digits is 193536, while the sum is 38.

The spelling of 72221443643 in words is "seventy-two billion, two hundred twenty-one million, four hundred forty-three thousand, six hundred forty-three".