28161906 has 8 divisors (see below), whose sum is σ = 56323824. Its totient is φ = 9387300.

The previous prime is 28161901. The next prime is 28161907. The reversal of 28161906 is 60916182.

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

28161906 is an admirable number.

It is not an unprimeable number, because it can be changed into a prime (28161901) 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, 2346820 + ... + 2346831.

It is an arithmetic number, because the mean of its divisors is an integer number (7040478).

Almost surely, 2^28161906 is an apocalyptic number.

28161906 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

28161906 is a wasteful number, since it uses less digits than its factorization.

28161906 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4693656.

The product of its (nonzero) digits is 5184, while the sum is 33.

The square root of 28161906 is about 5306.7792492245. The cubic root of 28161906 is about 304.2430607471.

The spelling of 28161906 in words is "twenty-eight million, one hundred sixty-one thousand, nine hundred six".