263097981 has 6 divisors (see below), whose sum is σ = 380030430. Its totient is φ = 175398648.

The previous prime is 263097977. The next prime is 263097983. The reversal of 263097981 is 189790362.

263097981 is a `hidden beast` number, since 2 + 630 + 9 + 7 + 9 + 8 + 1 = 666.

It can be written as a sum of positive squares in only one way, i.e., 256160025 + 6937956 = 16005^2 + 2634^2 .

It is not a de Polignac number, because 263097981 - 2² = 263097977 is a prime.

It is a super-2 number, since 2×263097981² = 138441095212552722, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (263097983) 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 5 ways as a sum of consecutive naturals, for example, 14616546 + ... + 14616563.

It is an arithmetic number, because the mean of its divisors is an integer number (63338405).

Almost surely, 2^263097981 is an apocalyptic number.

It is an amenable number.

263097981 is a deficient number, since it is larger than the sum of its proper divisors (116932449).

263097981 is a wasteful number, since it uses less digits than its factorization.

263097981 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 29233115 (or 29233112 counting only the distinct ones).

The product of its (nonzero) digits is 163296, while the sum is 45.

The square root of 263097981 is about 16220.2953425639. The cubic root of 263097981 is about 640.7754118715.

The spelling of 263097981 in words is "two hundred sixty-three million, ninety-seven thousand, nine hundred eighty-one".