20657029 has 4 divisors (see below), whose sum is σ = 20940076. Its totient is φ = 20373984.

The previous prime is 20657027. The next prime is 20657041. The reversal of 20657029 is 92075602.

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 11716929 + 8940100 = 3423^2 + 2990^2 .

It is a cyclic number.

It is not a de Polignac number, because 20657029 - 2¹ = 20657027 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20657027) 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 in 3 ways as a sum of consecutive naturals, for example, 141414 + ... + 141559.

It is an arithmetic number, because the mean of its divisors is an integer number (5235019).

Almost surely, 2^20657029 is an apocalyptic number.

It is an amenable number.

20657029 is a deficient number, since it is larger than the sum of its proper divisors (283047).

20657029 is an equidigital number, since it uses as much as digits as its factorization.

20657029 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 283046.

The product of its (nonzero) digits is 7560, while the sum is 31.

The square root of 20657029 is about 4545.0004400440. Note that the first 3 decimals coincide. The cubic root of 20657029 is about 274.3822120758.

The spelling of 20657029 in words is "twenty million, six hundred fifty-seven thousand, twenty-nine".