28192861 has 4 divisors (see below), whose sum is σ = 28339132. Its totient is φ = 28046592.

The previous prime is 28192847. The next prime is 28192883. The reversal of 28192861 is 16829182.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 4280761 + 23912100 = 2069^2 + 4890^2 .

It is a cyclic number.

It is not a de Polignac number, because 28192861 - 2¹³ = 28184669 is a prime.

It is a super-2 number, since 2×28192861² = 1589674822730642, which contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 28192861.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28192831) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 72846 + ... + 73231.

It is an arithmetic number, because the mean of its divisors is an integer number (7084783).

Almost surely, 2^28192861 is an apocalyptic number.

It is an amenable number.

28192861 is a deficient number, since it is larger than the sum of its proper divisors (146271).

28192861 is a wasteful number, since it uses less digits than its factorization.

28192861 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 146270.

The product of its digits is 13824, while the sum is 37.

The square root of 28192861 is about 5309.6950006568. The cubic root of 28192861 is about 304.3544925446.

The spelling of 28192861 in words is "twenty-eight million, one hundred ninety-two thousand, eight hundred sixty-one".