1968662081 has 2 divisors, whose sum is σ = 1968662082. Its totient is φ = 1968662080.

The previous prime is 1968662039. The next prime is 1968662141. The reversal of 1968662081 is 1802668691.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1772410000 + 196252081 = 42100^2 + 14009^2 .

It is a cyclic number.

It is not a de Polignac number, because 1968662081 - 2²² = 1964467777 is a prime.

It is a super-2 number, since 2×1968662081² = 7751260778334501122, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (1968662011) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 984331040 + 984331041.

It is an arithmetic number, because the mean of its divisors is an integer number (984331041).

Almost surely, 2^1968662081 is an apocalyptic number.

It is an amenable number.

1968662081 is a deficient number, since it is larger than the sum of its proper divisors (1).

1968662081 is an equidigital number, since it uses as much as digits as its factorization.

1968662081 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 248832, while the sum is 47.

The square root of 1968662081 is about 44369.6076272937. The cubic root of 1968662081 is about 1253.3058267802.

The spelling of 1968662081 in words is "one billion, nine hundred sixty-eight million, six hundred sixty-two thousand, eighty-one".