28981899 has 6 divisors (see below), whose sum is σ = 41862756. Its totient is φ = 19321260.

The previous prime is 28981891. The next prime is 28981907. The reversal of 28981899 is 99818982.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (28981891) and next prime (28981907).

It is not a de Polignac number, because 28981899 - 2³ = 28981891 is a prime.

It is not an unprimeable number, because it can be changed into a prime (28981891) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 1610097 + ... + 1610114.

It is an arithmetic number, because the mean of its divisors is an integer number (6977126).

Almost surely, 2^28981899 is an apocalyptic number.

28981899 is a deficient number, since it is larger than the sum of its proper divisors (12880857).

28981899 is a wasteful number, since it uses less digits than its factorization.

28981899 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3220217 (or 3220214 counting only the distinct ones).

The product of its digits is 746496, while the sum is 54.

The square root of 28981899 is about 5383.4839091429. The cubic root of 28981899 is about 307.1677474176.

The spelling of 28981899 in words is "twenty-eight million, nine hundred eighty-one thousand, eight hundred ninety-nine".