72439681 has 8 divisors (see below), whose sum is σ = 73504800. Its totient is φ = 71380320.

The previous prime is 72439613. The next prime is 72439693. The reversal of 72439681 is 18693427.

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

It is a cyclic number.

It is not a de Polignac number, because 72439681 - 2¹⁷ = 72308609 is a prime.

It is a super-2 number, since 2×72439681² = 10495014766763522, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (72439481) by changing a digit.

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 7 ways as a sum of consecutive naturals, for example, 28230 + ... + 30688.

It is an arithmetic number, because the mean of its divisors is an integer number (9188100).

Almost surely, 2^72439681 is an apocalyptic number.

It is an amenable number.

72439681 is a deficient number, since it is larger than the sum of its proper divisors (1065119).

72439681 is a wasteful number, since it uses less digits than its factorization.

72439681 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2879.

The product of its digits is 72576, while the sum is 40.

The square root of 72439681 is about 8511.1503922795. The cubic root of 72439681 is about 416.8618738295.

The spelling of 72439681 in words is "seventy-two million, four hundred thirty-nine thousand, six hundred eighty-one".