28994681 has 4 divisors (see below), whose sum is σ = 29042292. Its totient is φ = 28947072.

The previous prime is 28994653. The next prime is 28994689. The reversal of 28994681 is 18649982.

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 1000000 + 27994681 = 1000^2 + 5291^2 .

It is a cyclic number.

It is not a de Polignac number, because 28994681 - 2⁶ = 28994617 is a prime.

It is a super-2 number, since 2×28994681² = 1681383052583522, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (28994689) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 22880 + ... + 24113.

It is an arithmetic number, because the mean of its divisors is an integer number (7260573).

Almost surely, 2^28994681 is an apocalyptic number.

It is an amenable number.

28994681 is a deficient number, since it is larger than the sum of its proper divisors (47611).

28994681 is an equidigital number, since it uses as much as digits as its factorization.

28994681 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 47610.

The product of its digits is 248832, while the sum is 47.

The square root of 28994681 is about 5384.6709277355. The cubic root of 28994681 is about 307.2128979107.

The spelling of 28994681 in words is "twenty-eight million, nine hundred ninety-four thousand, six hundred eighty-one".