20472757 has 2 divisors, whose sum is σ = 20472758. Its totient is φ = 20472756.

The previous prime is 20472733. The next prime is 20472763. The reversal of 20472757 is 75727402.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 19018321 + 1454436 = 4361^2 + 1206^2 .

It is a cyclic number.

It is not a de Polignac number, because 20472757 - 2⁷ = 20472629 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20472797) 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, 10236378 + 10236379.

It is an arithmetic number, because the mean of its divisors is an integer number (10236379).

Almost surely, 2^20472757 is an apocalyptic number.

It is an amenable number.

20472757 is a deficient number, since it is larger than the sum of its proper divisors (1).

20472757 is an equidigital number, since it uses as much as digits as its factorization.

20472757 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 27440, while the sum is 34.

The square root of 20472757 is about 4524.6830828247. The cubic root of 20472757 is about 273.5638941346.

The spelling of 20472757 in words is "twenty million, four hundred seventy-two thousand, seven hundred fifty-seven".