72003581 has 8 divisors (see below), whose sum is σ = 78414840. Its totient is φ = 65716992.

The previous prime is 72003571. The next prime is 72003583. The reversal of 72003581 is 18530027.

It can be written as a sum of positive squares in 4 ways, for example, as 6943225 + 65060356 = 2635^2 + 8066^2 .

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-72003581 is a prime.

It is a super-2 number, since 2×72003581² = 10369031353647122, which contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 72003581.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (72003583) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 29960 + ... + 32273.

It is an arithmetic number, because the mean of its divisors is an integer number (9801855).

Almost surely, 2^72003581 is an apocalyptic number.

It is an amenable number.

72003581 is a deficient number, since it is larger than the sum of its proper divisors (6411259).

72003581 is a wasteful number, since it uses less digits than its factorization.

72003581 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 62335.

The product of its (nonzero) digits is 1680, while the sum is 26.

The square root of 72003581 is about 8485.4923840635. The cubic root of 72003581 is about 416.0236615147.

The spelling of 72003581 in words is "seventy-two million, three thousand, five hundred eighty-one".