2661513121 has 2 divisors, whose sum is σ = 2661513122. Its totient is φ = 2661513120.

The previous prime is 2661513089. The next prime is 2661513131. The reversal of 2661513121 is 1213151662.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 2617754896 + 43758225 = 51164^2 + 6615^2 .

It is a cyclic number.

It is not a de Polignac number, because 2661513121 - 2⁵ = 2661513089 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 2661513121.

It is not a weakly prime, because it can be changed into another prime (2661513131) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1330756560 + 1330756561.

It is an arithmetic number, because the mean of its divisors is an integer number (1330756561).

Almost surely, 2^2661513121 is an apocalyptic number.

It is an amenable number.

2661513121 is a deficient number, since it is larger than the sum of its proper divisors (1).

2661513121 is an equidigital number, since it uses as much as digits as its factorization.

2661513121 is an evil number, because the sum of its binary digits is even.

The product of its digits is 2160, while the sum is 28.

The square root of 2661513121 is about 51589.8548263125. The cubic root of 2661513121 is about 1385.8286553660.

Adding to 2661513121 its reverse (1213151662), we get a palindrome (3874664783).

The spelling of 2661513121 in words is "two billion, six hundred sixty-one million, five hundred thirteen thousand, one hundred twenty-one".