20459977 has 2 divisors, whose sum is σ = 20459978. Its totient is φ = 20459976.

The previous prime is 20459953. The next prime is 20459981. The reversal of 20459977 is 77995402.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 16232841 + 4227136 = 4029^2 + 2056^2 .

It is a cyclic number.

It is not a de Polignac number, because 20459977 - 2⁷ = 20459849 is a prime.

It is a super-2 number, since 2×20459977² = 837221317681058, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (20459947) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10229988 + 10229989.

It is an arithmetic number, because the mean of its divisors is an integer number (10229989).

Almost surely, 2^20459977 is an apocalyptic number.

It is an amenable number.

20459977 is a deficient number, since it is larger than the sum of its proper divisors (1).

20459977 is an equidigital number, since it uses as much as digits as its factorization.

20459977 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 158760, while the sum is 43.

The square root of 20459977 is about 4523.2706087520. The cubic root of 20459977 is about 273.5069587268.

The spelling of 20459977 in words is "twenty million, four hundred fifty-nine thousand, nine hundred seventy-seven".