247881561 has 8 divisors (see below), whose sum is σ = 330586080. Its totient is φ = 165215712.

The previous prime is 247881559. The next prime is 247881563. The reversal of 247881561 is 165188742.

It is an interprime number because it is at equal distance from previous prime (247881559) and next prime (247881563).

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

It is not a de Polignac number, because 247881561 - 2¹ = 247881559 is a prime.

It is a super-2 number, since 2×247881561² = 122890536567593442, which contains 22 as substring.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (247881563) 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, 12661 + ... + 25613.

It is an arithmetic number, because the mean of its divisors is an integer number (41323260).

Almost surely, 2^247881561 is an apocalyptic number.

It is an amenable number.

247881561 is a deficient number, since it is larger than the sum of its proper divisors (82704519).

247881561 is a wasteful number, since it uses less digits than its factorization.

247881561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 19335.

The product of its digits is 107520, while the sum is 42.

The square root of 247881561 is about 15744.2548569311. The cubic root of 247881561 is about 628.1760978901.

The spelling of 247881561 in words is "two hundred forty-seven million, eight hundred eighty-one thousand, five hundred sixty-one".