247949936981 has 2 divisors, whose sum is σ = 247949936982. Its totient is φ = 247949936980.

The previous prime is 247949936947. The next prime is 247949937097. The reversal of 247949936981 is 189639949742.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 167580521956 + 80369415025 = 409366^2 + 283495^2 .

It is a cyclic number.

It is not a de Polignac number, because 247949936981 - 2¹⁰ = 247949935957 is a prime.

It is a super-2 number, since 2×247949936981² (a number of 24 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (247949936881) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 123974968490 + 123974968491.

It is an arithmetic number, because the mean of its divisors is an integer number (123974968491).

Almost surely, 2^247949936981 is an apocalyptic number.

It is an amenable number.

247949936981 is a deficient number, since it is larger than the sum of its proper divisors (1).

247949936981 is an equidigital number, since it uses as much as digits as its factorization.

247949936981 is an evil number, because the sum of its binary digits is even.

The product of its digits is 211631616, while the sum is 71.

The spelling of 247949936981 in words is "two hundred forty-seven billion, nine hundred forty-nine million, nine hundred thirty-six thousand, nine hundred eighty-one".