247515205081 has 3 divisors (see below), whose sum is σ = 247515702591. Its totient is φ = 247514707572.

The previous prime is 247515205057. The next prime is 247515205087. The reversal of 247515205081 is 180502515742.

The square root of 247515205081 is 497509.

It is a perfect power (a square), and thus also a powerful number.

247515205081 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It can be written as a sum of positive squares in only one way, i.e., 246552964681 + 962240400 = 496541^2 + 31020^2 .

It is not a de Polignac number, because 247515205081 - 2⁷ = 247515204953 is a prime.

It is a super-2 number, since 2×247515205081² (a number of 24 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (247515205087) 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 in 2 ways as a sum of consecutive naturals, for example, 248755 + ... + 746263.

It is an arithmetic number, because the mean of its divisors is an integer number (82505234197).

Almost surely, 2^247515205081 is an apocalyptic number.

247515205081 is the 497509-th square number.

247515205081 is the 248755-th centered octagonal number.

It is an amenable number.

247515205081 is a deficient number, since it is larger than the sum of its proper divisors (497510).

247515205081 is an frugal number, since it uses more digits than its factorization.

247515205081 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 995018 (or 497509 counting only the distinct ones).

The product of its (nonzero) digits is 112000, while the sum is 40.

The spelling of 247515205081 in words is "two hundred forty-seven billion, five hundred fifteen million, two hundred five thousand, eighty-one".