20549377124657 has 2 divisors, whose sum is σ = 20549377124658. Its totient is φ = 20549377124656.

The previous prime is 20549377124503. The next prime is 20549377124663. The reversal of 20549377124657 is 75642177394502.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 17830426766881 + 2718950357776 = 4222609^2 + 1648924^2 .

It is a cyclic number.

It is not a de Polignac number, because 20549377124657 - 2³⁴ = 20532197255473 is a prime.

It is a super-2 number, since 2×20549377124657² (a number of 27 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 20549377124657.

It is not a weakly prime, because it can be changed into another prime (20549377124357) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10274688562328 + 10274688562329.

It is an arithmetic number, because the mean of its divisors is an integer number (10274688562329).

Almost surely, 2^{20549377124657} is an apocalyptic number.

It is an amenable number.

20549377124657 is a deficient number, since it is larger than the sum of its proper divisors (1).

20549377124657 is an equidigital number, since it uses as much as digits as its factorization.

20549377124657 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 88905600, while the sum is 62.

The spelling of 20549377124657 in words is "twenty trillion, five hundred forty-nine billion, three hundred seventy-seven million, one hundred twenty-four thousand, six hundred fifty-seven".