20757157 has 2 divisors, whose sum is σ = 20757158. Its totient is φ = 20757156.

The previous prime is 20757151. The next prime is 20757167. The reversal of 20757157 is 75175702.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 16434916 + 4322241 = 4054^2 + 2079^2 .

It is a cyclic number.

It is not a de Polignac number, because 20757157 - 2¹¹ = 20755109 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20757151) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10378578 + 10378579.

It is an arithmetic number, because the mean of its divisors is an integer number (10378579).

Almost surely, 2^20757157 is an apocalyptic number.

It is an amenable number.

20757157 is a deficient number, since it is larger than the sum of its proper divisors (1).

20757157 is an equidigital number, since it uses as much as digits as its factorization.

20757157 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 17150, while the sum is 34.

The square root of 20757157 is about 4556.0023046526. The cubic root of 20757157 is about 274.8248228698.

The spelling of 20757157 in words is "twenty million, seven hundred fifty-seven thousand, one hundred fifty-seven".