28896021 has 80 divisors (see below), whose sum is σ = 55617408. Its totient is φ = 14515200.

The previous prime is 28896019. The next prime is 28896029. The reversal of 28896021 is 12069882.

It is not a de Polignac number, because 28896021 - 2¹ = 28896019 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28896029) by changing a digit.

It is a polite number, since it can be written in 79 ways as a sum of consecutive naturals, for example, 255661 + ... + 255773.

Almost surely, 2^28896021 is an apocalyptic number.

28896021 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

It is an amenable number.

28896021 is a deficient number, since it is larger than the sum of its proper divisors (26721387).

28896021 is a wasteful number, since it uses less digits than its factorization.

28896021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 184 (or 175 counting only the distinct ones).

The product of its (nonzero) digits is 13824, while the sum is 36.

The square root of 28896021 is about 5375.5019300527. The cubic root of 28896021 is about 306.8640515394.

The spelling of 28896021 in words is "twenty-eight million, eight hundred ninety-six thousand, twenty-one".