28181590 has 8 divisors (see below), whose sum is σ = 50726880. Its totient is φ = 11272632.

The previous prime is 28181557. The next prime is 28181599. The reversal of 28181590 is 9518182.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28181599) by changing a digit.

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, 1409070 + ... + 1409089.

It is an arithmetic number, because the mean of its divisors is an integer number (6340860).

Almost surely, 2^28181590 is an apocalyptic number.

28181590 is a deficient number, since it is larger than the sum of its proper divisors (22545290).

28181590 is a wasteful number, since it uses less digits than its factorization.

28181590 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2818166.

The product of its (nonzero) digits is 5760, while the sum is 34.

The square root of 28181590 is about 5308.6335341592. The cubic root of 28181590 is about 304.3139286501.

The spelling of 28181590 in words is "twenty-eight million, one hundred eighty-one thousand, five hundred ninety".