28190772 has 18 divisors (see below), whose sum is σ = 71260098. Its totient is φ = 9396912.

The previous prime is 28190759. The next prime is 28190803. The reversal of 28190772 is 27709182.

It can be written as a sum of positive squares in only one way, i.e., 16941456 + 11249316 = 4116^2 + 3354^2 .

It is a tau number, because it is divible by the number of its divisors (18).

It is a Harshad number since it is a multiple of its sum of digits (36), and also a Moran number because the ratio is a prime number: 783077 = 28190772 / (2 + 8 + 1 + 9 + 0 + 7 + 7 + 2).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 391503 + ... + 391574.

Almost surely, 2^28190772 is an apocalyptic number.

It is an amenable number.

28190772 is an abundant number, since it is smaller than the sum of its proper divisors (43069326).

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

28190772 is a wasteful number, since it uses less digits than its factorization.

28190772 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 783087 (or 783082 counting only the distinct ones).

The product of its (nonzero) digits is 14112, while the sum is 36.

The square root of 28190772 is about 5309.4982813821. The cubic root of 28190772 is about 304.3469751304.

The spelling of 28190772 in words is "twenty-eight million, one hundred ninety thousand, seven hundred seventy-two".