20787757477573 has 2 divisors, whose sum is σ = 20787757477574. Its totient is φ = 20787757477572.

The previous prime is 20787757477537. The next prime is 20787757477601. The reversal of 20787757477573 is 37577475778702.

Together with previous prime (20787757477537) it forms an Ormiston pair, because they use the same digits, order apart.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 18257007843684 + 2530749633889 = 4272822^2 + 1590833^2 .

It is a cyclic number.

It is not a de Polignac number, because 20787757477573 - 2⁴¹ = 18588734222021 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 20787757477573.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20787757471573) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10393878738786 + 10393878738787.

It is an arithmetic number, because the mean of its divisors is an integer number (10393878738787).

Almost surely, 2^{20787757477573} is an apocalyptic number.

It is an amenable number.

20787757477573 is a deficient number, since it is larger than the sum of its proper divisors (1).

20787757477573 is an equidigital number, since it uses as much as digits as its factorization.

20787757477573 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 3953006400, while the sum is 76.

The spelling of 20787757477573 in words is "twenty trillion, seven hundred eighty-seven billion, seven hundred fifty-seven million, four hundred seventy-seven thousand, five hundred seventy-three".