203989891 has 12 divisors (see below), whose sum is σ = 237570528. Its totient is φ = 174645072.

The previous prime is 203989873. The next prime is 203989897. The reversal of 203989891 is 198989302.

It is not a de Polignac number, because 203989891 - 2⁵ = 203989859 is a prime.

It is a super-2 number, since 2×203989891² = 83223751260383762, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (49).

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (203989897) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 52870 + ... + 56596.

It is an arithmetic number, because the mean of its divisors is an integer number (19797544).

Almost surely, 2^203989891 is an apocalyptic number.

203989891 is a deficient number, since it is larger than the sum of its proper divisors (33580637).

203989891 is a wasteful number, since it uses less digits than its factorization.

203989891 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4858 (or 4851 counting only the distinct ones).

The product of its (nonzero) digits is 279936, while the sum is 49.

The square root of 203989891 is about 14282.5029669172. The cubic root of 203989891 is about 588.6668077842. Note that the first 3 decimals are identical.

The spelling of 203989891 in words is "two hundred three million, nine hundred eighty-nine thousand, eight hundred ninety-one".