100943989 has 4 divisors (see below), whose sum is σ = 100964556. Its totient is φ = 100923424.

The previous prime is 100943971. The next prime is 100943993. The reversal of 100943989 is 989349001.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 989349001 = 67 ⋅14766403.

It can be written as a sum of positive squares in 2 ways, for example, as 57608100 + 43335889 = 7590^2 + 6583^2 .

It is a cyclic number.

It is not a de Polignac number, because 100943989 - 2⁷ = 100943861 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (100943939) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1857 + ... + 14329.

It is an arithmetic number, because the mean of its divisors is an integer number (25241139).

Almost surely, 2^100943989 is an apocalyptic number.

It is an amenable number.

100943989 is a deficient number, since it is larger than the sum of its proper divisors (20567).

100943989 is an equidigital number, since it uses as much as digits as its factorization.

100943989 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20566.

The product of its (nonzero) digits is 69984, while the sum is 43.

The square root of 100943989 is about 10047.0885832663. The cubic root of 100943989 is about 465.6148478125.

The spelling of 100943989 in words is "one hundred million, nine hundred forty-three thousand, nine hundred eighty-nine".