20707474636777 has 2 divisors, whose sum is σ = 20707474636778. Its totient is φ = 20707474636776.

The previous prime is 20707474636759. The next prime is 20707474636801. The reversal of 20707474636777 is 77763647470702.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 16033970011536 + 4673504625241 = 4004244^2 + 2161829^2 .

It is a cyclic number.

It is not a de Polignac number, because 20707474636777 - 2¹⁹ = 20707474112489 is a prime.

It is a super-3 number, since 3×20707474636777³ (a number of 41 digits) contains 333 as substring.

It is not a weakly prime, because it can be changed into another prime (20707474636477) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10353737318388 + 10353737318389.

It is an arithmetic number, because the mean of its divisors is an integer number (10353737318389).

Almost surely, 2^{20707474636777} is an apocalyptic number.

It is an amenable number.

20707474636777 is a deficient number, since it is larger than the sum of its proper divisors (1).

20707474636777 is an equidigital number, since it uses as much as digits as its factorization.

20707474636777 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 406594944, while the sum is 67.

The spelling of 20707474636777 in words is "twenty trillion, seven hundred seven billion, four hundred seventy-four million, six hundred thirty-six thousand, seven hundred seventy-seven".