201888989 has 2 divisors, whose sum is σ = 201888990. Its totient is φ = 201888988.

The previous prime is 201888977. The next prime is 201889027. The reversal of 201888989 is 989888102.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 163968025 + 37920964 = 12805^2 + 6158^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-201888989 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 201888989.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (201888959) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 100944494 + 100944495.

It is an arithmetic number, because the mean of its divisors is an integer number (100944495).

Almost surely, 2^201888989 is an apocalyptic number.

It is an amenable number.

201888989 is a deficient number, since it is larger than the sum of its proper divisors (1).

201888989 is an equidigital number, since it uses as much as digits as its factorization.

201888989 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 663552, while the sum is 53.

The square root of 201888989 is about 14208.7645134966. The cubic root of 201888989 is about 586.6389271420.

The spelling of 201888989 in words is "two hundred one million, eight hundred eighty-eight thousand, nine hundred eighty-nine".