28249551 has 24 divisors (see below), whose sum is σ = 45152640. Its totient is φ = 16875600.

The previous prime is 28249549. The next prime is 28249591. The reversal of 28249551 is 15594282.

It is not a de Polignac number, because 28249551 - 2¹ = 28249549 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28249541) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 5020 + ... + 9038.

It is an arithmetic number, because the mean of its divisors is an integer number (1881360).

Almost surely, 2^28249551 is an apocalyptic number.

28249551 is a deficient number, since it is larger than the sum of its proper divisors (16903089).

28249551 is a wasteful number, since it uses less digits than its factorization.

28249551 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4107 (or 4104 counting only the distinct ones).

The product of its digits is 28800, while the sum is 36.

The square root of 28249551 is about 5315.0306678325. The cubic root of 28249551 is about 304.5583538985.

The spelling of 28249551 in words is "twenty-eight million, two hundred forty-nine thousand, five hundred fifty-one".