20761055761 has 4 divisors (see below), whose sum is σ = 20912596452. Its totient is φ = 20609515072.

The previous prime is 20761055753. The next prime is 20761055771. The reversal of 20761055761 is 16755016702.

It is a happy number.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 5694966225 + 15066089536 = 75465^2 + 122744^2 .

It is a cyclic number.

It is not a de Polignac number, because 20761055761 - 2³ = 20761055753 is a prime.

It is a super-2 number, since 2×20761055761² (a number of 21 digits) contains 22 as substring.

It is a Smith number, since the sum of its digits (40) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20761055771) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 75770140 + ... + 75770413.

It is an arithmetic number, because the mean of its divisors is an integer number (5228149113).

Almost surely, 2^20761055761 is an apocalyptic number.

It is an amenable number.

20761055761 is a deficient number, since it is larger than the sum of its proper divisors (151540691).

20761055761 is a wasteful number, since it uses less digits than its factorization.

20761055761 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 151540690.

The product of its (nonzero) digits is 88200, while the sum is 40.

The spelling of 20761055761 in words is "twenty billion, seven hundred sixty-one million, fifty-five thousand, seven hundred sixty-one".