20777103757649 has 8 divisors (see below), whose sum is σ = 20824399358952. Its totient is φ = 20729851810560.

The previous prime is 20777103757639. The next prime is 20777103757687. The reversal of 20777103757649 is 94675730177702.

It can be written as a sum of positive squares in 4 ways, for example, as 1869695247424 + 18907408510225 = 1367368^2 + 4348265^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 20777103757649 - 2⁴ = 20777103757633 is a prime.

It is a super-2 number, since 2×20777103757649² (a number of 27 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20777103757639) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 9960482 + ... + 11864459.

It is an arithmetic number, because the mean of its divisors is an integer number (2603049919869).

Almost surely, 2^{20777103757649} is an apocalyptic number.

It is an amenable number.

20777103757649 is a deficient number, since it is larger than the sum of its proper divisors (47295601303).

20777103757649 is a wasteful number, since it uses less digits than its factorization.

20777103757649 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 21827107.

The product of its (nonzero) digits is 108909360, while the sum is 65.

The spelling of 20777103757649 in words is "twenty trillion, seven hundred seventy-seven billion, one hundred three million, seven hundred fifty-seven thousand, six hundred forty-nine".