20429569 has 2 divisors, whose sum is σ = 20429570. Its totient is φ = 20429568.

The previous prime is 20429557. The next prime is 20429593. The reversal of 20429569 is 96592402.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 15116544 + 5313025 = 3888^2 + 2305^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20429569 is a prime.

It is a super-2 number, since 2×20429569² = 834734579051522, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (20429599) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10214784 + 10214785.

It is an arithmetic number, because the mean of its divisors is an integer number (10214785).

Almost surely, 2^20429569 is an apocalyptic number.

It is an amenable number.

20429569 is a deficient number, since it is larger than the sum of its proper divisors (1).

20429569 is an equidigital number, since it uses as much as digits as its factorization.

20429569 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 38880, while the sum is 37.

The square root of 20429569 is about 4519.9080742865. The cubic root of 20429569 is about 273.3713944949.

It can be divided in two parts, 2042 and 9569, that added together give a palindrome (11611).

The spelling of 20429569 in words is "twenty million, four hundred twenty-nine thousand, five hundred sixty-nine".