20761057 has 2 divisors, whose sum is σ = 20761058. Its totient is φ = 20761056.

The previous prime is 20761043. The next prime is 20761067. The reversal of 20761057 is 75016702.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 20575296 + 185761 = 4536^2 + 431^2 .

It is a cyclic number.

It is not a de Polignac number, because 20761057 - 2¹⁵ = 20728289 is a prime.

It is not a weakly prime, because it can be changed into another prime (20761067) 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 as a sum of consecutive naturals, namely, 10380528 + 10380529.

It is an arithmetic number, because the mean of its divisors is an integer number (10380529).

Almost surely, 2^20761057 is an apocalyptic number.

It is an amenable number.

20761057 is a deficient number, since it is larger than the sum of its proper divisors (1).

20761057 is an equidigital number, since it uses as much as digits as its factorization.

20761057 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 2940, while the sum is 28.

The square root of 20761057 is about 4556.4302913575. The cubic root of 20761057 is about 274.8420337959.

Adding to 20761057 its reverse (75016702), we get a palindrome (95777759).

The spelling of 20761057 in words is "twenty million, seven hundred sixty-one thousand, fifty-seven".