20017129 has 4 divisors (see below), whose sum is σ = 21836880. Its totient is φ = 18197380.

The previous prime is 20017117. The next prime is 20017133. The reversal of 20017129 is 92171002.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 20017129 - 2⁷ = 20017001 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20017169) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 909859 + ... + 909880.

It is an arithmetic number, because the mean of its divisors is an integer number (5459220).

Almost surely, 2^20017129 is an apocalyptic number.

It is an amenable number.

20017129 is a deficient number, since it is larger than the sum of its proper divisors (1819751).

20017129 is a wasteful number, since it uses less digits than its factorization.

20017129 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1819750.

The product of its (nonzero) digits is 252, while the sum is 22.

The square root of 20017129 is about 4474.0506255517. The cubic root of 20017129 is about 271.5192316462.

The spelling of 20017129 in words is "twenty million, seventeen thousand, one hundred twenty-nine".