247981879 has 2 divisors, whose sum is σ = 247981880. Its totient is φ = 247981878.

The previous prime is 247981841. The next prime is 247981889. The reversal of 247981879 is 978189742.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 247981879 - 2⁷ = 247981751 is a prime.

It is a super-2 number, since 2×247981879² = 122990024624741282, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (247981889) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 123990939 + 123990940.

It is an arithmetic number, because the mean of its divisors is an integer number (123990940).

Almost surely, 2^247981879 is an apocalyptic number.

247981879 is a deficient number, since it is larger than the sum of its proper divisors (1).

247981879 is an equidigital number, since it uses as much as digits as its factorization.

247981879 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 2032128, while the sum is 55.

The square root of 247981879 is about 15747.4403951880. The cubic root of 247981879 is about 628.2608276973.

The spelling of 247981879 in words is "two hundred forty-seven million, nine hundred eighty-one thousand, eight hundred seventy-nine".