28969139 has 4 divisors (see below), whose sum is σ = 30673224. Its totient is φ = 27265056.

The previous prime is 28969117. The next prime is 28969141. The reversal of 28969139 is 93196982.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 93196982 = 2 ⋅46598491.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-28969139 is a prime.

It is a super-2 number, since 2×28969139² = 1678422028802642, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 28969093 and 28969102.

It is not an unprimeable number, because it can be changed into a prime (28969189) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 852017 + ... + 852050.

It is an arithmetic number, because the mean of its divisors is an integer number (7668306).

Almost surely, 2^28969139 is an apocalyptic number.

28969139 is a deficient number, since it is larger than the sum of its proper divisors (1704085).

28969139 is a wasteful number, since it uses less digits than its factorization.

28969139 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1704084.

The product of its digits is 209952, while the sum is 47.

The square root of 28969139 is about 5382.2986725004. The cubic root of 28969139 is about 307.1226613932.

The spelling of 28969139 in words is "twenty-eight million, nine hundred sixty-nine thousand, one hundred thirty-nine".