247243861 has 2 divisors, whose sum is σ = 247243862. Its totient is φ = 247243860.

The previous prime is 247243849. The next prime is 247243877. The reversal of 247243861 is 168342742.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 228916900 + 18326961 = 15130^2 + 4281^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-247243861 is a prime.

It is a super-2 number, since 2×247243861² = 122259053604374642, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 247243861.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (247243811) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 123621930 + 123621931.

It is an arithmetic number, because the mean of its divisors is an integer number (123621931).

Almost surely, 2^247243861 is an apocalyptic number.

It is an amenable number.

247243861 is a deficient number, since it is larger than the sum of its proper divisors (1).

247243861 is an equidigital number, since it uses as much as digits as its factorization.

247243861 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 64512, while the sum is 37.

The square root of 247243861 is about 15723.9899834616. The cubic root of 247243861 is about 627.6369534357.

The spelling of 247243861 in words is "two hundred forty-seven million, two hundred forty-three thousand, eight hundred sixty-one".