20099977 has 2 divisors, whose sum is σ = 20099978. Its totient is φ = 20099976.

The previous prime is 20099941. The next prime is 20099983. The reversal of 20099977 is 77999002.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 17397241 + 2702736 = 4171^2 + 1644^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20099977 is a prime.

It is not a weakly prime, because it can be changed into another prime (20099077) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10049988 + 10049989.

It is an arithmetic number, because the mean of its divisors is an integer number (10049989).

Almost surely, 2^20099977 is an apocalyptic number.

It is an amenable number.

20099977 is a deficient number, since it is larger than the sum of its proper divisors (1).

20099977 is an equidigital number, since it uses as much as digits as its factorization.

20099977 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 71442, while the sum is 43.

The square root of 20099977 is about 4483.2997892178. The cubic root of 20099977 is about 271.8933089709.

The spelling of 20099977 in words is "twenty million, ninety-nine thousand, nine hundred seventy-seven".