20501797 has 2 divisors, whose sum is σ = 20501798. Its totient is φ = 20501796.

The previous prime is 20501791. The next prime is 20501807. The reversal of 20501797 is 79710502.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 16695396 + 3806401 = 4086^2 + 1951^2 .

It is a cyclic number.

It is not a de Polignac number, because 20501797 - 2¹¹ = 20499749 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20501791) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10250898 + 10250899.

It is an arithmetic number, because the mean of its divisors is an integer number (10250899).

Almost surely, 2^20501797 is an apocalyptic number.

It is an amenable number.

20501797 is a deficient number, since it is larger than the sum of its proper divisors (1).

20501797 is an equidigital number, since it uses as much as digits as its factorization.

20501797 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 4410, while the sum is 31.

The square root of 20501797 is about 4527.8910101724. The cubic root of 20501797 is about 273.6931804538.

The spelling of 20501797 in words is "twenty million, five hundred one thousand, seven hundred ninety-seven".