20570129 has 4 divisors (see below), whose sum is σ = 20591076. Its totient is φ = 20549184.

The previous prime is 20570117. The next prime is 20570167. The reversal of 20570129 is 92107502.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 9909904 + 10660225 = 3148^2 + 3265^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20570129 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 20570098 and 20570107.

It is not an unprimeable number, because it can be changed into a prime (20570029) 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, 8924 + ... + 10989.

It is an arithmetic number, because the mean of its divisors is an integer number (5147769).

Almost surely, 2^20570129 is an apocalyptic number.

It is an amenable number.

20570129 is a deficient number, since it is larger than the sum of its proper divisors (20947).

20570129 is a wasteful number, since it uses less digits than its factorization.

20570129 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20946.

The product of its (nonzero) digits is 1260, while the sum is 26.

The square root of 20570129 is about 4535.4304095642. The cubic root of 20570129 is about 273.9969142033.

The spelling of 20570129 in words is "twenty million, five hundred seventy thousand, one hundred twenty-nine".