28971290 has 16 divisors (see below), whose sum is σ = 53947080. Its totient is φ = 11188800.

The previous prime is 28971287. The next prime is 28971307. The reversal of 28971290 is 9217982.

It can be written as a sum of positive squares in 4 ways, for example, as 28398241 + 573049 = 5329^2 + 757^2 .

It is a Curzon number.

It is an unprimeable number.

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 7 ways as a sum of consecutive naturals, for example, 49661 + ... + 50240.

Almost surely, 2^28971290 is an apocalyptic number.

28971290 is a deficient number, since it is larger than the sum of its proper divisors (24975790).

28971290 is a wasteful number, since it uses less digits than its factorization.

28971290 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 99937.

The product of its (nonzero) digits is 18144, while the sum is 38.

The square root of 28971290 is about 5382.4984904782. The cubic root of 28971290 is about 307.1302626374.

The spelling of 28971290 in words is "twenty-eight million, nine hundred seventy-one thousand, two hundred ninety".