72003540 has 144 divisors (see below), whose sum is σ = 247060800. Its totient is φ = 15579648.

The previous prime is 72003527. The next prime is 72003563. The reversal of 72003540 is 4530027.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (21).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 55216 + ... + 56504.

It is an arithmetic number, because the mean of its divisors is an integer number (1715700).

Almost surely, 2^72003540 is an apocalyptic number.

72003540 is a gapful number since it is divisible by the number (70) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 72003540, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (123530400).

72003540 is an abundant number, since it is smaller than the sum of its proper divisors (175057260).

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

72003540 is a wasteful number, since it uses less digits than its factorization.

72003540 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1334 (or 1325 counting only the distinct ones).

The product of its (nonzero) digits is 840, while the sum is 21.

The square root of 72003540 is about 8485.4899681751. The cubic root of 72003540 is about 416.0235825512.

Adding to 72003540 its reverse (4530027), we get a palindrome (76533567).

The spelling of 72003540 in words is "seventy-two million, three thousand, five hundred forty".