72189538 has 8 divisors (see below), whose sum is σ = 108325980. Its totient is φ = 36080880.

The previous prime is 72189529. The next prime is 72189541. The reversal of 72189538 is 83598127.

It can be written as a sum of positive squares in 2 ways, for example, as 69839449 + 2350089 = 8357^2 + 1533^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a super-2 number, since 2×72189538² = 10422658793306888, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 72189494 and 72189503.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1708 + ... + 12136.

Almost surely, 2^72189538 is an apocalyptic number.

72189538 is a deficient number, since it is larger than the sum of its proper divisors (36136442).

72189538 is a wasteful number, since it uses less digits than its factorization.

72189538 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13892.

The product of its digits is 120960, while the sum is 43.

The square root of 72189538 is about 8496.4426673756. The cubic root of 72189538 is about 416.3814956082.

It can be divided in two parts, 72189 and 538, that added together give a palindrome (72727).

The spelling of 72189538 in words is "seventy-two million, one hundred eighty-nine thousand, five hundred thirty-eight".