20009929 has 2 divisors, whose sum is σ = 20009930. Its totient is φ = 20009928.

The previous prime is 20009923. The next prime is 20009939. The reversal of 20009929 is 92990002.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 14478025 + 5531904 = 3805^2 + 2352^2 .

It is a cyclic number.

It is not a de Polignac number, because 20009929 - 2¹¹ = 20007881 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 20009929.

It is not a weakly prime, because it can be changed into another prime (20009923) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10004964 + 10004965.

It is an arithmetic number, because the mean of its divisors is an integer number (10004965).

Almost surely, 2^20009929 is an apocalyptic number.

It is an amenable number.

20009929 is a deficient number, since it is larger than the sum of its proper divisors (1).

20009929 is an equidigital number, since it uses as much as digits as its factorization.

20009929 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2916, while the sum is 31.

The square root of 20009929 is about 4473.2459132044. The cubic root of 20009929 is about 271.4866733157.

The spelling of 20009929 in words is "twenty million, nine thousand, nine hundred twenty-nine".