247328509 has 4 divisors (see below), whose sum is σ = 255306880. Its totient is φ = 239350140.

The previous prime is 247328483. The next prime is 247328519. The reversal of 247328509 is 905823742.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 247328509 - 2¹³ = 247320317 is a prime.

It is a super-2 number, since 2×247328509² = 122342782728326162, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (247328519) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3989139 + ... + 3989200.

It is an arithmetic number, because the mean of its divisors is an integer number (63826720).

Almost surely, 2^247328509 is an apocalyptic number.

It is an amenable number.

247328509 is a deficient number, since it is larger than the sum of its proper divisors (7978371).

247328509 is an equidigital number, since it uses as much as digits as its factorization.

247328509 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7978370.

The product of its (nonzero) digits is 120960, while the sum is 40.

The square root of 247328509 is about 15726.6814363361. The cubic root of 247328509 is about 627.7085725390.

The spelling of 247328509 in words is "two hundred forty-seven million, three hundred twenty-eight thousand, five hundred nine".