28911938 has 8 divisors (see below), whose sum is σ = 47310480. Its totient is φ = 13141780.

The previous prime is 28911919. The next prime is 28911941. The reversal of 28911938 is 83911982.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 28911895 and 28911904.

It is an unprimeable number.

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 3 ways as a sum of consecutive naturals, for example, 657068 + ... + 657111.

It is an arithmetic number, because the mean of its divisors is an integer number (5913810).

Almost surely, 2^28911938 is an apocalyptic number.

28911938 is a deficient number, since it is larger than the sum of its proper divisors (18398542).

28911938 is a wasteful number, since it uses less digits than its factorization.

28911938 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1314192.

The product of its digits is 31104, while the sum is 41.

The square root of 28911938 is about 5376.9822391375. The cubic root of 28911938 is about 306.9203852304.

The spelling of 28911938 in words is "twenty-eight million, nine hundred eleven thousand, nine hundred thirty-eight".