28592981 has 4 divisors (see below), whose sum is σ = 28887852. Its totient is φ = 28298112.

The previous prime is 28592969. The next prime is 28592983. The reversal of 28592981 is 18929582.

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 20702500 + 7890481 = 4550^2 + 2809^2 .

It is a cyclic number.

It is not a de Polignac number, because 28592981 - 2¹⁰ = 28591957 is a prime.

It is a super-2 number, since 2×28592981² = 1635117124932722, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28592983) 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, 147290 + ... + 147483.

It is an arithmetic number, because the mean of its divisors is an integer number (7221963).

Almost surely, 2^28592981 is an apocalyptic number.

It is an amenable number.

28592981 is a deficient number, since it is larger than the sum of its proper divisors (294871).

28592981 is an equidigital number, since it uses as much as digits as its factorization.

28592981 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 294870.

The product of its digits is 103680, while the sum is 44.

The square root of 28592981 is about 5347.2405032877. The cubic root of 28592981 is about 305.7875588417.

The spelling of 28592981 in words is "twenty-eight million, five hundred ninety-two thousand, nine hundred eighty-one".