72231520 has 48 divisors (see below), whose sum is σ = 171270288. Its totient is φ = 28787200.

The previous prime is 72231499. The next prime is 72231539. The reversal of 72231520 is 2513227.

It is a junction number, because it is equal to n+sod(n) for n = 72231491 and 72231500.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 54870 + ... + 56170.

It is an arithmetic number, because the mean of its divisors is an integer number (3568131).

Almost surely, 2^72231520 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 72231520, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (85635144).

72231520 is an abundant number, since it is smaller than the sum of its proper divisors (99038768).

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

72231520 is a wasteful number, since it uses less digits than its factorization.

72231520 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1663 (or 1655 counting only the distinct ones).

The product of its (nonzero) digits is 840, while the sum is 22.

The square root of 72231520 is about 8498.9128716560. The cubic root of 72231520 is about 416.4621958542.

Adding to 72231520 its reverse (2513227), we get a palindrome (74744747).

The spelling of 72231520 in words is "seventy-two million, two hundred thirty-one thousand, five hundred twenty".