72240381 has 12 divisors (see below), whose sum is σ = 104429052. Its totient is φ = 48122496.

The previous prime is 72240373. The next prime is 72240397. The reversal of 72240381 is 18304227.

It can be written as a sum of positive squares in 2 ways, for example, as 12425625 + 59814756 = 3525^2 + 7734^2 .

It is not a de Polignac number, because 72240381 - 2³ = 72240373 is a prime.

It is a super-2 number, since 2×72240381² = 10437345294050322, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (72240481) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 13735 + ... + 18251.

It is an arithmetic number, because the mean of its divisors is an integer number (8702421).

Almost surely, 2^72240381 is an apocalyptic number.

It is an amenable number.

72240381 is a deficient number, since it is larger than the sum of its proper divisors (32188671).

72240381 is a wasteful number, since it uses less digits than its factorization.

72240381 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6300 (or 6297 counting only the distinct ones).

The product of its (nonzero) digits is 2688, while the sum is 27.

The square root of 72240381 is about 8499.4341576366. The cubic root of 72240381 is about 416.4792249879.

The spelling of 72240381 in words is "seventy-two million, two hundred forty thousand, three hundred eighty-one".