264138673661 has 2 divisors, whose sum is σ = 264138673662. Its totient is φ = 264138673660.

The previous prime is 264138673649. The next prime is 264138673691. The reversal of 264138673661 is 166376831462.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 236798051161 + 27340622500 = 486619^2 + 165350^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-264138673661 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (264138673691) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 132069336830 + 132069336831.

It is an arithmetic number, because the mean of its divisors is an integer number (132069336831).

Almost surely, 2^264138673661 is an apocalyptic number.

It is an amenable number.

264138673661 is a deficient number, since it is larger than the sum of its proper divisors (1).

264138673661 is an equidigital number, since it uses as much as digits as its factorization.

264138673661 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 5225472, while the sum is 53.

The spelling of 264138673661 in words is "two hundred sixty-four billion, one hundred thirty-eight million, six hundred seventy-three thousand, six hundred sixty-one".