20657051 has 2 divisors, whose sum is σ = 20657052. Its totient is φ = 20657050.

The previous prime is 20657041. The next prime is 20657053. The reversal of 20657051 is 15075602.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 20657051 - 2¹⁴ = 20640667 is a prime.

Together with 20657053, it forms a pair of twin primes.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 20657051.

It is not a weakly prime, because it can be changed into another prime (20657053) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10328525 + 10328526.

It is an arithmetic number, because the mean of its divisors is an integer number (10328526).

Almost surely, 2^20657051 is an apocalyptic number.

20657051 is a deficient number, since it is larger than the sum of its proper divisors (1).

20657051 is an equidigital number, since it uses as much as digits as its factorization.

20657051 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 2100, while the sum is 26.

The square root of 20657051 is about 4545.0028602851. The cubic root of 20657051 is about 274.3823094826.

Subtracting from 20657051 its sum of digits (26), we obtain a square (20657025 = 4545²).

The spelling of 20657051 in words is "twenty million, six hundred fifty-seven thousand, fifty-one".