20000009977 has 2 divisors, whose sum is σ = 20000009978. Its totient is φ = 20000009976.

The previous prime is 20000009963. The next prime is 20000009999. The reversal of 20000009977 is 77990000002.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 14956311616 + 5043698361 = 122296^2 + 71019^2 .

It is a cyclic number.

It is not a de Polignac number, because 20000009977 - 2¹⁵ = 19999977209 is a prime.

It is not a weakly prime, because it can be changed into another prime (20000009917) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10000004988 + 10000004989.

It is an arithmetic number, because the mean of its divisors is an integer number (10000004989).

Almost surely, 2^20000009977 is an apocalyptic number.

It is an amenable number.

20000009977 is a deficient number, since it is larger than the sum of its proper divisors (1).

20000009977 is an equidigital number, since it uses as much as digits as its factorization.

20000009977 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 7938, while the sum is 34.

Adding to 20000009977 its reverse (77990000002), we get a palindrome (97990009979).

The spelling of 20000009977 in words is "twenty billion, nine thousand, nine hundred seventy-seven".