28690890 has 64 divisors (see below), whose sum is σ = 73598976. Its totient is φ = 7140672.

The previous prime is 28690877. The next prime is 28690897. The reversal of 28690890 is 9809682.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (28690897) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 29187 + ... + 30153.

It is an arithmetic number, because the mean of its divisors is an integer number (1149984).

Almost surely, 2^28690890 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 28690890, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (36799488).

28690890 is an abundant number, since it is smaller than the sum of its proper divisors (44908086).

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

28690890 is a wasteful number, since it uses less digits than its factorization.

28690890 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1043.

The product of its (nonzero) digits is 62208, while the sum is 42.

The square root of 28690890 is about 5356.3877753576. The cubic root of 28690890 is about 306.1361903918.

The spelling of 28690890 in words is "twenty-eight million, six hundred ninety thousand, eight hundred ninety".