20552873681 has 2 divisors, whose sum is σ = 20552873682. Its totient is φ = 20552873680.

The previous prime is 20552873659. The next prime is 20552873687. The reversal of 20552873681 is 18637825502.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 13363360000 + 7189513681 = 115600^2 + 84791^2 .

It is a cyclic number.

It is not a de Polignac number, because 20552873681 - 2¹⁸ = 20552611537 is a prime.

It is a super-2 number, since 2×20552873681² (a number of 21 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (20552873687) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10276436840 + 10276436841.

It is an arithmetic number, because the mean of its divisors is an integer number (10276436841).

Almost surely, 2^20552873681 is an apocalyptic number.

It is an amenable number.

20552873681 is a deficient number, since it is larger than the sum of its proper divisors (1).

20552873681 is an equidigital number, since it uses as much as digits as its factorization.

20552873681 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 806400, while the sum is 47.

The spelling of 20552873681 in words is "twenty billion, five hundred fifty-two million, eight hundred seventy-three thousand, six hundred eighty-one".