28038690 has 64 divisors (see below), whose sum is σ = 75513600. Its totient is φ = 7402752.

The previous prime is 28038683. The next prime is 28038691. The reversal of 28038690 is 9683082.

It is a super-2 number, since 2×28038690² = 1572336273832200, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28038691) 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 31 ways as a sum of consecutive naturals, for example, 30051 + ... + 30969.

It is an arithmetic number, because the mean of its divisors is an integer number (1179900).

Almost surely, 2^28038690 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 28038690, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (37756800).

28038690 is an abundant number, since it is smaller than the sum of its proper divisors (47474910).

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

28038690 is a wasteful number, since it uses less digits than its factorization.

28038690 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1048 (or 1042 counting only the distinct ones).

The product of its (nonzero) digits is 20736, while the sum is 36.

The square root of 28038690 is about 5295.1572214619. The cubic root of 28038690 is about 303.7986966584.

The spelling of 28038690 in words is "twenty-eight million, thirty-eight thousand, six hundred ninety".