20428693 has 2 divisors, whose sum is σ = 20428694. Its totient is φ = 20428692.

The previous prime is 20428687. The next prime is 20428697. The reversal of 20428693 is 39682402.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 16957924 + 3470769 = 4118^2 + 1863^2 .

It is a cyclic number.

It is not a de Polignac number, because 20428693 - 2¹⁷ = 20297621 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20428697) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10214346 + 10214347.

It is an arithmetic number, because the mean of its divisors is an integer number (10214347).

Almost surely, 2^20428693 is an apocalyptic number.

It is an amenable number.

20428693 is a deficient number, since it is larger than the sum of its proper divisors (1).

20428693 is an equidigital number, since it uses as much as digits as its factorization.

20428693 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 20736, while the sum is 34.

The square root of 20428693 is about 4519.8111686220. The cubic root of 20428693 is about 273.3674871394.

The spelling of 20428693 in words is "twenty million, four hundred twenty-eight thousand, six hundred ninety-three".