28749666 has 64 divisors (see below), whose sum is σ = 65817216. Its totient is φ = 8294400.

The previous prime is 28749649. The next prime is 28749689. The reversal of 28749666 is 66694782.

It is a super-2 number, since 2×28749666² = 1653086590223112, which contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 148866 + ... + 149058.

It is an arithmetic number, because the mean of its divisors is an integer number (1028394).

Almost surely, 2^28749666 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 28749666, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (32908608).

28749666 is an abundant number, since it is smaller than the sum of its proper divisors (37067550).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

28749666 is a wasteful number, since it uses less digits than its factorization.

28749666 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 307.

The product of its digits is 870912, while the sum is 48.

The square root of 28749666 is about 5361.8715016308. The cubic root of 28749666 is about 306.3450974419.

Subtracting 28749666 from its reverse (66694782), we obtain a triangular number (37945116 = T₈₇₁₁).

It can be divided in two parts, 287496 and 66, that multiplied together give a 4-th power (18974736 = 66⁴).

The spelling of 28749666 in words is "twenty-eight million, seven hundred forty-nine thousand, six hundred sixty-six".