28038780 has 324 divisors, whose sum is σ = 114653448. Its totient is φ = 5483520.

The previous prime is 28038757. The next prime is 28038809. The reversal of 28038780 is 8783082.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 107 ways as a sum of consecutive naturals, for example, 1649332 + ... + 1649348.

Almost surely, 2^28038780 is an apocalyptic number.

28038780 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 28038780, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (57326724).

28038780 is an abundant number, since it is smaller than the sum of its proper divisors (86614668).

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

28038780 is a wasteful number, since it uses less digits than its factorization.

28038780 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 74 (or 45 counting only the distinct ones).

The product of its (nonzero) digits is 21504, while the sum is 36.

The square root of 28038780 is about 5295.1657197863. The cubic root of 28038780 is about 303.7990217075.

Adding to 28038780 its sum of digits (36), we get a triangular number (28038816 = T₇₄₈₈).

It can be divided in two parts, 280 and 38780, that added together give a triangular number (39060 = T₂₇₉).

The spelling of 28038780 in words is "twenty-eight million, thirty-eight thousand, seven hundred eighty".