263121806116 has 81 divisors (see below), whose sum is σ = 506019996153. Its totient is φ = 119661909120.

The previous prime is 263121806113. The next prime is 263121806161. The reversal of 263121806116 is 611608121362.

It is a happy number.

The square root of 263121806116 is 512954.

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

It can be written as a sum of positive squares in 13 ways, for example, as 261315216100 + 1806590016 = 511190^2 + 42504^2 .

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (263121806113) by changing a digit.

It is a polite number, since it can be written in 26 ways as a sum of consecutive naturals, for example, 1453711546 + ... + 1453711726.

Almost surely, 2^263121806116 is an apocalyptic number.

263121806116 is a gapful number since it is divisible by the number (26) formed by its first and last digit.

263121806116 is the 512954-th square number.

It is an amenable number.

263121806116 is a deficient number, since it is larger than the sum of its proper divisors (242898190037).

263121806116 is a wasteful number, since it uses less digits than its factorization.

263121806116 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 610 (or 305 counting only the distinct ones).

The product of its (nonzero) digits is 20736, while the sum is 37.

Adding to 263121806116 its reverse (611608121362), we get a palindrome (874729927478).

The spelling of 263121806116 in words is "two hundred sixty-three billion, one hundred twenty-one million, eight hundred six thousand, one hundred sixteen".