20928237 has 16 divisors (see below), whose sum is σ = 30730752. Its totient is φ = 12563120.

The previous prime is 20928223. The next prime is 20928239. The reversal of 20928237 is 73282902.

It is a cyclic number.

It is not a de Polignac number, because 20928237 - 2⁸ = 20927981 is a prime.

It is a super-2 number, since 2×20928237² = 875982207856338, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (33).

It is a junction number, because it is equal to n+sod(n) for n = 20928198 and 20928207.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20928239) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 568 + ... + 6494.

It is an arithmetic number, because the mean of its divisors is an integer number (1920672).

Almost surely, 2^20928237 is an apocalyptic number.

It is an amenable number.

20928237 is a deficient number, since it is larger than the sum of its proper divisors (9802515).

20928237 is a wasteful number, since it uses less digits than its factorization.

20928237 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6048.

The product of its (nonzero) digits is 12096, while the sum is 33.

The square root of 20928237 is about 4574.7390089490. The cubic root of 20928237 is about 275.5777912369.

The spelling of 20928237 in words is "twenty million, nine hundred twenty-eight thousand, two hundred thirty-seven".