20720883877 has 2 divisors, whose sum is σ = 20720883878. Its totient is φ = 20720883876.

The previous prime is 20720883847. The next prime is 20720883889. The reversal of 20720883877 is 77838802702.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 19928686561 + 792197316 = 141169^2 + 28146^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20720883877 is a prime.

It is a super-2 number, since 2×20720883877² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20720883847) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10360441938 + 10360441939.

It is an arithmetic number, because the mean of its divisors is an integer number (10360441939).

Almost surely, 2^20720883877 is an apocalyptic number.

It is an amenable number.

20720883877 is a deficient number, since it is larger than the sum of its proper divisors (1).

20720883877 is an equidigital number, since it uses as much as digits as its factorization.

20720883877 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 2107392, while the sum is 52.

The spelling of 20720883877 in words is "twenty billion, seven hundred twenty million, eight hundred eighty-three thousand, eight hundred seventy-seven".