247978265 has 4 divisors (see below), whose sum is σ = 297573924. Its totient is φ = 198382608.

The previous prime is 247978261. The next prime is 247978267. The reversal of 247978265 is 562879742.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 97081609 + 150896656 = 9853^2 + 12284^2 .

It is a cyclic number.

It is not a de Polignac number, because 247978265 - 2² = 247978261 is a prime.

It is a super-2 number, since 2×247978265² = 122986439824820450, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (247978261) 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, 24797822 + ... + 24797831.

It is an arithmetic number, because the mean of its divisors is an integer number (74393481).

Almost surely, 2^247978265 is an apocalyptic number.

It is an amenable number.

247978265 is a deficient number, since it is larger than the sum of its proper divisors (49595659).

247978265 is an equidigital number, since it uses as much as digits as its factorization.

247978265 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 49595658.

The product of its digits is 1693440, while the sum is 50.

The square root of 247978265 is about 15747.3256459629. The cubic root of 247978265 is about 628.2577756656.

The spelling of 247978265 in words is "two hundred forty-seven million, nine hundred seventy-eight thousand, two hundred sixty-five".