2781217256 has 8 divisors (see below), whose sum is σ = 5214782370. Its totient is φ = 1390608624.

The previous prime is 2781217217. The next prime is 2781217267. The reversal of 2781217256 is 6527121872.

It can be written as a sum of positive squares in only one way, i.e., 1907068900 + 874148356 = 43670^2 + 29566^2 .

It is a tau number, because it is divible by the number of its divisors (8).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 173826071 + ... + 173826086.

Almost surely, 2^2781217256 is an apocalyptic number.

It is an amenable number.

2781217256 is a deficient number, since it is larger than the sum of its proper divisors (2433565114).

2781217256 is a wasteful number, since it uses less digits than its factorization.

2781217256 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 347652163 (or 347652159 counting only the distinct ones).

The product of its digits is 94080, while the sum is 41.

The square root of 2781217256 is about 52737.2473305158. The cubic root of 2781217256 is about 1406.3010631901.

The spelling of 2781217256 in words is "two billion, seven hundred eighty-one million, two hundred seventeen thousand, two hundred fifty-six".