28943551 has 16 divisors (see below), whose sum is σ = 36119104. Its totient is φ = 22581504.

The previous prime is 28943543. The next prime is 28943557. The reversal of 28943551 is 15534982.

It is a cyclic number.

It is not a de Polignac number, because 28943551 - 2³ = 28943543 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 28943551.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28943557) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 4465 + ... + 8821.

It is an arithmetic number, because the mean of its divisors is an integer number (2257444).

Almost surely, 2^28943551 is an apocalyptic number.

28943551 is a deficient number, since it is larger than the sum of its proper divisors (7175553).

28943551 is a wasteful number, since it uses less digits than its factorization.

28943551 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4450.

The product of its digits is 43200, while the sum is 37.

The square root of 28943551 is about 5379.9210960757. The cubic root of 28943551 is about 307.0322091640.

The spelling of 28943551 in words is "twenty-eight million, nine hundred forty-three thousand, five hundred fifty-one".