28897331 has 8 divisors (see below), whose sum is σ = 30985920. Its totient is φ = 26851968.

The previous prime is 28897313. The next prime is 28897343. The reversal of 28897331 is 13379882.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 28897331 - 2¹⁴ = 28880947 is a prime.

It is a super-2 number, since 2×28897331² = 1670111477847122, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (28897391) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 9416 + ... + 12101.

It is an arithmetic number, because the mean of its divisors is an integer number (3873240).

Almost surely, 2^28897331 is an apocalyptic number.

28897331 is a deficient number, since it is larger than the sum of its proper divisors (2088589).

28897331 is a wasteful number, since it uses less digits than its factorization.

28897331 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 21613.

The product of its digits is 72576, while the sum is 41.

The square root of 28897331 is about 5375.6237777583. The cubic root of 28897331 is about 306.8686886926.

It can be divided in two parts, 288 and 97331, that multiplied together give a triangular number (28031328 = T₇₄₈₇).

The spelling of 28897331 in words is "twenty-eight million, eight hundred ninety-seven thousand, three hundred thirty-one".