20429109 has 6 divisors (see below), whose sum is σ = 29508726. Its totient is φ = 13619400.

The previous prime is 20429081. The next prime is 20429117. The reversal of 20429109 is 90192402.

It can be written as a sum of positive squares in only one way, i.e., 20277009 + 152100 = 4503^2 + 390^2 .

It is not a de Polignac number, because 20429109 - 2⁵ = 20429077 is a prime.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20429119) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 1134942 + ... + 1134959.

It is an arithmetic number, because the mean of its divisors is an integer number (4918121).

Almost surely, 2^20429109 is an apocalyptic number.

It is an amenable number.

20429109 is a deficient number, since it is larger than the sum of its proper divisors (9079617).

20429109 is a wasteful number, since it uses less digits than its factorization.

20429109 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2269907 (or 2269904 counting only the distinct ones).

The product of its (nonzero) digits is 1296, while the sum is 27.

The square root of 20429109 is about 4519.8571880094. The cubic root of 20429109 is about 273.3693427012.

The spelling of 20429109 in words is "twenty million, four hundred twenty-nine thousand, one hundred nine".