72539881 has 8 divisors (see below), whose sum is σ = 74925000. Its totient is φ = 70192512.

The previous prime is 72539837. The next prime is 72539897. The reversal of 72539881 is 18893527.

It can be written as a sum of positive squares in 4 ways, for example, as 24098281 + 48441600 = 4909^2 + 6960^2 .

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 72539881 - 2¹³ = 72531689 is a prime.

It is a super-2 number, since 2×72539881² = 10524068670988322, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (72539821) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 5506 + ... + 13243.

It is an arithmetic number, because the mean of its divisors is an integer number (9365625).

Almost surely, 2^72539881 is an apocalyptic number.

It is an amenable number.

72539881 is a deficient number, since it is larger than the sum of its proper divisors (2385119).

72539881 is a wasteful number, since it uses less digits than its factorization.

72539881 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 18875.

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

The square root of 72539881 is about 8517.0347539505. The cubic root of 72539881 is about 417.0539891413.

The spelling of 72539881 in words is "seventy-two million, five hundred thirty-nine thousand, eight hundred eighty-one".