263221557321256 has 16 divisors (see below), whose sum is σ = 493570344460500. Its totient is φ = 131602798798464.

The previous prime is 263221557321221. The next prime is 263221557321269. The reversal of 263221557321256 is 652123755122362.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 201030826389156 + 62190730932100 = 14178534^2 + 7886110^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 997342581 + ... + 997606468.

Almost surely, 2^{263221557321256} is an apocalyptic number.

It is an amenable number.

263221557321256 is a deficient number, since it is larger than the sum of its proper divisors (230348787139244).

263221557321256 is a wasteful number, since it uses less digits than its factorization.

263221557321256 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1994965548 (or 1994965544 counting only the distinct ones).

The product of its digits is 9072000, while the sum is 52.

The spelling of 263221557321256 in words is "two hundred sixty-three trillion, two hundred twenty-one billion, five hundred fifty-seven million, three hundred twenty-one thousand, two hundred fifty-six".