2106720761 has 2 divisors, whose sum is σ = 2106720762. Its totient is φ = 2106720760.

The previous prime is 2106720751. The next prime is 2106720799. The reversal of 2106720761 is 1670276012.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 2103965161 + 2755600 = 45869^2 + 1660^2 .

It is a cyclic number.

It is not a de Polignac number, because 2106720761 - 2¹⁴ = 2106704377 is a prime.

It is not a weakly prime, because it can be changed into another prime (2106720751) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1053360380 + 1053360381.

It is an arithmetic number, because the mean of its divisors is an integer number (1053360381).

Almost surely, 2^2106720761 is an apocalyptic number.

It is an amenable number.

2106720761 is a deficient number, since it is larger than the sum of its proper divisors (1).

2106720761 is an equidigital number, since it uses as much as digits as its factorization.

2106720761 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 7056, while the sum is 32.

The square root of 2106720761 is about 45899.0278873093. The cubic root of 2106720761 is about 1281.9438160237.

Adding to 2106720761 its reverse (1670276012), we get a palindrome (3776996773).

The spelling of 2106720761 in words is "two billion, one hundred six million, seven hundred twenty thousand, seven hundred sixty-one".