28724290 has 72 divisors (see below), whose sum is σ = 63166716. Its totient is φ = 9374400.

The previous prime is 28724281. The next prime is 28724303. The reversal of 28724290 is 9242782.

It can be written as a sum of positive squares in 2 ways, for example, as 24910081 + 3814209 = 4991^2 + 1953^2 .

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 35 ways as a sum of consecutive naturals, for example, 470860 + ... + 470920.

Almost surely, 2^28724290 is an apocalyptic number.

28724290 is an abundant number, since it is smaller than the sum of its proper divisors (34442426).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

28724290 is a wasteful number, since it uses less digits than its factorization.

28724290 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 144 (or 106 counting only the distinct ones).

The product of its (nonzero) digits is 16128, while the sum is 34.

The square root of 28724290 is about 5359.5046412892. The cubic root of 28724290 is about 306.2549386959.

The spelling of 28724290 in words is "twenty-eight million, seven hundred twenty-four thousand, two hundred ninety".