247740865 has 8 divisors (see below), whose sum is σ = 297379368. Its totient is φ = 198132480.

The previous prime is 247740839. The next prime is 247740887. The reversal of 247740865 is 568047742.

It can be written as a sum of positive squares in 4 ways, for example, as 98485776 + 149255089 = 9924^2 + 12217^2 .

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

It is a de Polignac number, because none of the positive numbers 2^k-247740865 is a prime.

It is a super-2 number, since 2×247740865² = 122751072381896450, which contains 22 as substring.

It is a Duffinian number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 19209 + ... + 29401.

It is an arithmetic number, because the mean of its divisors is an integer number (37172421).

Almost surely, 2^247740865 is an apocalyptic number.

It is an amenable number.

247740865 is a deficient number, since it is larger than the sum of its proper divisors (49638503).

247740865 is a wasteful number, since it uses less digits than its factorization.

247740865 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15059.

The product of its (nonzero) digits is 376320, while the sum is 43.

The square root of 247740865 is about 15739.7860531838. The cubic root of 247740865 is about 628.0572258088.

The spelling of 247740865 in words is "two hundred forty-seven million, seven hundred forty thousand, eight hundred sixty-five".