20028737 has 4 divisors (see below), whose sum is σ = 21206916. Its totient is φ = 18850560.

The previous prime is 20028731. The next prime is 20028739. The reversal of 20028737 is 73782002.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 12138256 + 7890481 = 3484^2 + 2809^2 .

It is a cyclic number.

It is not a de Polignac number, because 20028737 - 2¹⁶ = 19963201 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20028731) by changing a digit.

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 3 ways as a sum of consecutive naturals, for example, 589064 + ... + 589097.

It is an arithmetic number, because the mean of its divisors is an integer number (5301729).

Almost surely, 2^20028737 is an apocalyptic number.

It is an amenable number.

20028737 is a deficient number, since it is larger than the sum of its proper divisors (1178179).

20028737 is a wasteful number, since it uses less digits than its factorization.

20028737 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1178178.

The product of its (nonzero) digits is 4704, while the sum is 29.

The square root of 20028737 is about 4475.3476959897. The cubic root of 20028737 is about 271.5717064740.

The spelling of 20028737 in words is "twenty million, twenty-eight thousand, seven hundred thirty-seven".