100043989 has 2 divisors, whose sum is σ = 100043990. Its totient is φ = 100043988.

The previous prime is 100043981. The next prime is 100044001. The reversal of 100043989 is 989340001.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 55621764 + 44422225 = 7458^2 + 6665^2 .

It is a cyclic number.

It is not a de Polignac number, because 100043989 - 2³ = 100043981 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (100043981) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 50021994 + 50021995.

It is an arithmetic number, because the mean of its divisors is an integer number (50021995).

Almost surely, 2^100043989 is an apocalyptic number.

It is an amenable number.

100043989 is a deficient number, since it is larger than the sum of its proper divisors (1).

100043989 is an equidigital number, since it uses as much as digits as its factorization.

100043989 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 7776, while the sum is 34.

The square root of 100043989 is about 10002.1992081742. The cubic root of 100043989 is about 464.2269330012.

The spelling of 100043989 in words is "one hundred million, forty-three thousand, nine hundred eighty-nine".