28020745 has 8 divisors (see below), whose sum is σ = 34709760. Its totient is φ = 21693360.

The previous prime is 28020731. The next prime is 28020749. The reversal of 28020745 is 54702082.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a de Polignac number, because none of the positive numbers 2^k-28020745 is a prime.

It is not an unprimeable number, because it can be changed into a prime (28020749) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 90235 + ... + 90544.

It is an arithmetic number, because the mean of its divisors is an integer number (4338720).

Almost surely, 2^28020745 is an apocalyptic number.

It is an amenable number.

28020745 is a deficient number, since it is larger than the sum of its proper divisors (6689015).

28020745 is a wasteful number, since it uses less digits than its factorization.

28020745 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 180815.

The product of its (nonzero) digits is 4480, while the sum is 28.

The square root of 28020745 is about 5293.4624774338. The cubic root of 28020745 is about 303.7338715773.

It can be divided in two parts, 280 and 20745, that added together give a square (21025 = 145²).

The spelling of 28020745 in words is "twenty-eight million, twenty thousand, seven hundred forty-five".