72245309 has 8 divisors (see below), whose sum is σ = 73670520. Its totient is φ = 70834176.

The previous prime is 72245297. The next prime is 72245357. The reversal of 72245309 is 90354227.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 4644025 + 67601284 = 2155^2 + 8222^2 .

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 72245309 - 2²⁰ = 71196733 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (72245209) 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, 7157 + ... + 13989.

It is an arithmetic number, because the mean of its divisors is an integer number (9208815).

Almost surely, 2^72245309 is an apocalyptic number.

It is an amenable number.

72245309 is a deficient number, since it is larger than the sum of its proper divisors (1425211).

72245309 is a wasteful number, since it uses less digits than its factorization.

72245309 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7039.

The product of its (nonzero) digits is 15120, while the sum is 32.

The square root of 72245309 is about 8499.7240543444. The cubic root of 72245309 is about 416.4886950513.

The spelling of 72245309 in words is "seventy-two million, two hundred forty-five thousand, three hundred nine".