28540390 has 16 divisors (see below), whose sum is σ = 52568208. Its totient is φ = 11150496.

The previous prime is 28540361. The next prime is 28540411. The reversal of 28540390 is 9304582.

It is a super-2 number, since 2×28540390² = 1629107722704200, which contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 32757 + ... + 33616.

It is an arithmetic number, because the mean of its divisors is an integer number (3285513).

Almost surely, 2^28540390 is an apocalyptic number.

28540390 is a deficient number, since it is larger than the sum of its proper divisors (24027818).

28540390 is a wasteful number, since it uses less digits than its factorization.

28540390 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 66423.

The product of its (nonzero) digits is 8640, while the sum is 31.

The square root of 28540390 is about 5342.3206567933. The cubic root of 28540390 is about 305.5999656785.

The spelling of 28540390 in words is "twenty-eight million, five hundred forty thousand, three hundred ninety".