20128469 has 2 divisors, whose sum is σ = 20128470. Its totient is φ = 20128468.

The previous prime is 20128453. The next prime is 20128477. The reversal of 20128469 is 96482102.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 15697444 + 4431025 = 3962^2 + 2105^2 .

It is a cyclic number.

It is not a de Polignac number, because 20128469 - 2⁴ = 20128453 is a prime.

It is a super-2 number, since 2×20128469² = 810310528567922, which contains 22 as substring.

It is equal to p_1278257 and since 20128469 and 1278257 have the same sum of digits, it is a Honaker prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20128439) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10064234 + 10064235.

It is an arithmetic number, because the mean of its divisors is an integer number (10064235).

Almost surely, 2^20128469 is an apocalyptic number.

It is an amenable number.

20128469 is a deficient number, since it is larger than the sum of its proper divisors (1).

20128469 is an equidigital number, since it uses as much as digits as its factorization.

20128469 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 6912, while the sum is 32.

The square root of 20128469 is about 4486.4762341954. The cubic root of 20128469 is about 272.0217191783.

The spelling of 20128469 in words is "twenty million, one hundred twenty-eight thousand, four hundred sixty-nine".