28493681 has 8 divisors (see below), whose sum is σ = 29526528. Its totient is φ = 27468000.

The previous prime is 28493659. The next prime is 28493713. The reversal of 28493681 is 18639482.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 28493681 - 2¹⁰ = 28492657 is a prime.

It is a super-2 number, since 2×28493681² = 1623779713859522, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (28493281) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 7076 + ... + 10346.

It is an arithmetic number, because the mean of its divisors is an integer number (3690816).

Almost surely, 2^28493681 is an apocalyptic number.

It is an amenable number.

28493681 is a deficient number, since it is larger than the sum of its proper divisors (1032847).

28493681 is a wasteful number, since it uses less digits than its factorization.

28493681 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3583.

The product of its digits is 82944, while the sum is 41.

The square root of 28493681 is about 5337.9472646327. The cubic root of 28493681 is about 305.4331604019.

The spelling of 28493681 in words is "twenty-eight million, four hundred ninety-three thousand, six hundred eighty-one".