20551767077 has 2 divisors, whose sum is σ = 20551767078. Its totient is φ = 20551767076.

The previous prime is 20551767013. The next prime is 20551767079. The reversal of 20551767077 is 77076715502.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 19385271361 + 1166495716 = 139231^2 + 34154^2 .

It is a cyclic number.

It is not a de Polignac number, because 20551767077 - 2⁶ = 20551767013 is a prime.

It is a super-2 number, since 2×20551767077² (a number of 21 digits) contains 22 as substring.

Together with 20551767079, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20551767079) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10275883538 + 10275883539.

It is an arithmetic number, because the mean of its divisors is an integer number (10275883539).

Almost surely, 2^20551767077 is an apocalyptic number.

It is an amenable number.

20551767077 is a deficient number, since it is larger than the sum of its proper divisors (1).

20551767077 is an equidigital number, since it uses as much as digits as its factorization.

20551767077 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 720300, while the sum is 47.

The spelling of 20551767077 in words is "twenty billion, five hundred fifty-one million, seven hundred sixty-seven thousand, seventy-seven".