20923429 has 2 divisors, whose sum is σ = 20923430. Its totient is φ = 20923428.

The previous prime is 20923417. The next prime is 20923459. The reversal of 20923429 is 92432902.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 19228225 + 1695204 = 4385^2 + 1302^2 .

It is a cyclic number.

It is not a de Polignac number, because 20923429 - 2²¹ = 18826277 is a prime.

It is a super-2 number, since 2×20923429² = 875579762236082, which contains 22 as substring.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 20923429.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20923459) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10461714 + 10461715.

It is an arithmetic number, because the mean of its divisors is an integer number (10461715).

Almost surely, 2^20923429 is an apocalyptic number.

It is an amenable number.

20923429 is a deficient number, since it is larger than the sum of its proper divisors (1).

20923429 is an equidigital number, since it uses as much as digits as its factorization.

20923429 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 7776, while the sum is 31.

The square root of 20923429 is about 4574.2134843053. The cubic root of 20923429 is about 275.5566861067.

The spelling of 20923429 in words is "twenty million, nine hundred twenty-three thousand, four hundred twenty-nine".