1988356081 has 2 divisors, whose sum is σ = 1988356082. Its totient is φ = 1988356080.

The previous prime is 1988356039. The next prime is 1988356147. The reversal of 1988356081 is 1806538891.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1943399056 + 44957025 = 44084^2 + 6705^2 .

It is an emirp because it is prime and its reverse (1806538891) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1988356081 - 2²⁹ = 1451485169 is a prime.

It is a super-2 number, since 2×1988356081² = 7907119809699357122, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (1988356001) 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 as a sum of consecutive naturals, namely, 994178040 + 994178041.

It is an arithmetic number, because the mean of its divisors is an integer number (994178041).

Almost surely, 2^1988356081 is an apocalyptic number.

It is an amenable number.

1988356081 is a deficient number, since it is larger than the sum of its proper divisors (1).

1988356081 is an equidigital number, since it uses as much as digits as its factorization.

1988356081 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 414720, while the sum is 49.

The square root of 1988356081 is about 44590.9865443679. The cubic root of 1988356081 is about 1257.4712196800.

The spelling of 1988356081 in words is "one billion, nine hundred eighty-eight million, three hundred fifty-six thousand, eighty-one".