20730735761 has 4 divisors (see below), whose sum is σ = 20790136500. Its totient is φ = 20671335024.

The previous prime is 20730735691. The next prime is 20730735763. The reversal of 20730735761 is 16753703702.

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 5410485136 + 15320250625 = 73556^2 + 123775^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20730735761 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20730735763) 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, 29699846 + ... + 29700543.

It is an arithmetic number, because the mean of its divisors is an integer number (5197534125).

Almost surely, 2^20730735761 is an apocalyptic number.

It is an amenable number.

20730735761 is a deficient number, since it is larger than the sum of its proper divisors (59400739).

20730735761 is an equidigital number, since it uses as much as digits as its factorization.

20730735761 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 59400738.

The product of its (nonzero) digits is 185220, while the sum is 41.

The spelling of 20730735761 in words is "twenty billion, seven hundred thirty million, seven hundred thirty-five thousand, seven hundred sixty-one".