28043691 has 12 divisors (see below), whose sum is σ = 40489848. Its totient is φ = 17257344.

The previous prime is 28043681. The next prime is 28043711. The reversal of 28043691 is 19634082.

It is not a de Polignac number, because 28043691 - 2⁶ = 28043627 is a prime.

It is not an unprimeable number, because it can be changed into a prime (28043621) 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, 27150 + ... + 28163.

It is an arithmetic number, because the mean of its divisors is an integer number (3374154).

Almost surely, 2^28043691 is an apocalyptic number.

28043691 is a deficient number, since it is larger than the sum of its proper divisors (12446157).

28043691 is a wasteful number, since it uses less digits than its factorization.

28043691 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 55342 (or 55329 counting only the distinct ones).

The product of its (nonzero) digits is 10368, while the sum is 33.

The square root of 28043691 is about 5295.6294243461. The cubic root of 28043691 is about 303.8167574994.

The spelling of 28043691 in words is "twenty-eight million, forty-three thousand, six hundred ninety-one".