28039967 has 4 divisors (see below), whose sum is σ = 29259120. Its totient is φ = 26820816.

The previous prime is 28039961. The next prime is 28039981. The reversal of 28039967 is 76993082.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 76993082 = 2 ⋅38496541.

It is a cyclic number.

It is not a de Polignac number, because 28039967 - 2⁴ = 28039951 is a prime.

It is a super-2 number, since 2×28039967² = 1572479498722178, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28039961) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 609542 + ... + 609587.

It is an arithmetic number, because the mean of its divisors is an integer number (7314780).

Almost surely, 2^28039967 is an apocalyptic number.

28039967 is a deficient number, since it is larger than the sum of its proper divisors (1219153).

28039967 is a wasteful number, since it uses less digits than its factorization.

28039967 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1219152.

The product of its (nonzero) digits is 163296, while the sum is 44.

The square root of 28039967 is about 5295.2778019666. The cubic root of 28039967 is about 303.8033086790.

The spelling of 28039967 in words is "twenty-eight million, thirty-nine thousand, nine hundred sixty-seven".