72221436432 has 50 divisors (see below), whose sum is σ = 209029793918. Its totient is φ = 24073811712.

The previous prime is 72221436431. The next prime is 72221436433. The reversal of 72221436432 is 23463412227.

72221436432 is a `hidden beast` number, since 7 + 2 + 2 + 2 + 1 + 4 + 3 + 643 + 2 = 666.

It is an interprime number because it is at equal distance from previous prime (72221436431) and next prime (72221436433).

It can be written as a sum of positive squares in only one way, i.e., 38128029696 + 34093406736 = 195264^2 + 184644^2 .

It is a Harshad number since it is a multiple of its sum of digits (36).

It is not an unprimeable number, because it can be changed into a prime (72221436431) by changing a digit.

It is a polite number, since it can be written in 9 ways as a sum of consecutive naturals, for example, 27861913 + ... + 27864504.

Almost surely, 2^72221436432 is an apocalyptic number.

72221436432 is a gapful number since it is divisible by the number (72) formed by its first and last digit.

It is an amenable number.

72221436432 is an abundant number, since it is smaller than the sum of its proper divisors (136808357486).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

72221436432 is a wasteful number, since it uses less digits than its factorization.

72221436432 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 55726437 (or 55726422 counting only the distinct ones).

The product of its digits is 96768, while the sum is 36.

Adding to 72221436432 its reverse (23463412227), we get a palindrome (95684848659).

The spelling of 72221436432 in words is "seventy-two billion, two hundred twenty-one million, four hundred thirty-six thousand, four hundred thirty-two".