28485981 has 12 divisors (see below), whose sum is σ = 41726880. Its totient is φ = 18722760.

The previous prime is 28485979. The next prime is 28485991. The reversal of 28485981 is 18958482.

It is a happy number.

It is not a de Polignac number, because 28485981 - 2¹ = 28485979 is a prime.

It is a super-2 number, since 2×28485981² = 1622902227064722, which contains 22 as substring.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28485911) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 21651 + ... + 22928.

It is an arithmetic number, because the mean of its divisors is an integer number (3477240).

Almost surely, 2^28485981 is an apocalyptic number.

It is an amenable number.

28485981 is a deficient number, since it is larger than the sum of its proper divisors (13240899).

28485981 is a wasteful number, since it uses less digits than its factorization.

28485981 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 44656 (or 44653 counting only the distinct ones).

The product of its digits is 184320, while the sum is 45.

The square root of 28485981 is about 5337.2259648623. The cubic root of 28485981 is about 305.4056449771.

The spelling of 28485981 in words is "twenty-eight million, four hundred eighty-five thousand, nine hundred eighty-one".