28779390 has 48 divisors (see below), whose sum is σ = 75428496. Its totient is φ = 7612800.

The previous prime is 28779349. The next prime is 28779391. The reversal of 28779390 is 9397782.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28779391) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 10570 + ... + 13010.

It is an arithmetic number, because the mean of its divisors is an integer number (1571427).

Almost surely, 2^28779390 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 28779390, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (37714248).

28779390 is an abundant number, since it is smaller than the sum of its proper divisors (46649106).

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

28779390 is a wasteful number, since it uses less digits than its factorization.

28779390 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2585 (or 2582 counting only the distinct ones).

The product of its (nonzero) digits is 190512, while the sum is 45.

The square root of 28779390 is about 5364.6425789609. The cubic root of 28779390 is about 306.4506368170.

The spelling of 28779390 in words is "twenty-eight million, seven hundred seventy-nine thousand, three hundred ninety".