28919751 has 24 divisors (see below), whose sum is σ = 45278064. Its totient is φ = 16369920.

The previous prime is 28919747. The next prime is 28919819. The reversal of 28919751 is 15791982.

It is not a de Polignac number, because 28919751 - 2² = 28919747 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28919701) 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, 15741 + ... + 17481.

It is an arithmetic number, because the mean of its divisors is an integer number (1886586).

Almost surely, 2^28919751 is an apocalyptic number.

28919751 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

28919751 is a deficient number, since it is larger than the sum of its proper divisors (16358313).

28919751 is a wasteful number, since it uses less digits than its factorization.

28919751 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1871 (or 1864 counting only the distinct ones).

The product of its digits is 45360, while the sum is 42.

The square root of 28919751 is about 5377.7087128256. The cubic root of 28919751 is about 306.9480295550.

The spelling of 28919751 in words is "twenty-eight million, nine hundred nineteen thousand, seven hundred fifty-one".