28618638 has 16 divisors (see below), whose sum is σ = 58176336. Its totient is φ = 9383040.

The previous prime is 28618637. The next prime is 28618643. The reversal of 28618638 is 83681682.

It is a self number, because there is not a number n which added to its sum of digits gives 28618638.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28618631) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 38731 + ... + 39462.

It is an arithmetic number, because the mean of its divisors is an integer number (3636021).

Almost surely, 2^28618638 is an apocalyptic number.

28618638 is an abundant number, since it is smaller than the sum of its proper divisors (29557698).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

28618638 is a wasteful number, since it uses less digits than its factorization.

28618638 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 78259.

The product of its digits is 110592, while the sum is 42.

The square root of 28618638 is about 5349.6390532446. The cubic root of 28618638 is about 305.8789944042.

The spelling of 28618638 in words is "twenty-eight million, six hundred eighteen thousand, six hundred thirty-eight".