28190191 has 8 divisors (see below), whose sum is σ = 29500544. Its totient is φ = 26904960.

The previous prime is 28190179. The next prime is 28190209. The reversal of 28190191 is 19109182.

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

It is a cyclic number.

It is not a de Polignac number, because 28190191 - 2¹¹ = 28188143 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (31).

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28190161) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3966 + ... + 8491.

It is an arithmetic number, because the mean of its divisors is an integer number (3687568).

Almost surely, 2^28190191 is an apocalyptic number.

28190191 is a deficient number, since it is larger than the sum of its proper divisors (1310353).

28190191 is a wasteful number, since it uses less digits than its factorization.

28190191 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12561.

The product of its (nonzero) digits is 1296, while the sum is 31.

The square root of 28190191 is about 5309.4435678327. The cubic root of 28190191 is about 304.3448842948.

The spelling of 28190191 in words is "twenty-eight million, one hundred ninety thousand, one hundred ninety-one".