261011211424213 has 4 divisors (see below), whose sum is σ = 261229997017548. Its totient is φ = 260792425830880.

The previous prime is 261011211424127. The next prime is 261011211424217. The reversal of 261011211424213 is 312424112110162.

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 214571579620644 + 46439631803569 = 14648262^2 + 6814663^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-261011211424213 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (261011211424217) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 109392794878 + ... + 109392797263.

It is an arithmetic number, because the mean of its divisors is an integer number (65307499254387).

Almost surely, 2^{261011211424213} is an apocalyptic number.

It is an amenable number.

261011211424213 is a deficient number, since it is larger than the sum of its proper divisors (218785593335).

261011211424213 is a wasteful number, since it uses less digits than its factorization.

261011211424213 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 218785593334.

The product of its (nonzero) digits is 4608, while the sum is 31.

Adding to 261011211424213 its reverse (312424112110162), we get a palindrome (573435323534375).

The spelling of 261011211424213 in words is "two hundred sixty-one trillion, eleven billion, two hundred eleven million, four hundred twenty-four thousand, two hundred thirteen".