28791388 has 6 divisors (see below), whose sum is σ = 50384936. Its totient is φ = 14395692.

The previous prime is 28791379. The next prime is 28791397. The reversal of 28791388 is 88319782.

It is an interprime number because it is at equal distance from previous prime (28791379) and next prime (28791397).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3598920 + ... + 3598927.

Almost surely, 2^28791388 is an apocalyptic number.

It is an amenable number.

28791388 is a deficient number, since it is larger than the sum of its proper divisors (21593548).

28791388 is a wasteful number, since it uses less digits than its factorization.

28791388 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7197851 (or 7197849 counting only the distinct ones).

The product of its digits is 193536, while the sum is 46.

The square root of 28791388 is about 5365.7607102814. The cubic root of 28791388 is about 306.4932168706.

The spelling of 28791388 in words is "twenty-eight million, seven hundred ninety-one thousand, three hundred eighty-eight".