261215435452616 has 8 divisors (see below), whose sum is σ = 489778941473670. Its totient is φ = 130607717726304.

The previous prime is 261215435452613. The next prime is 261215435452627. The reversal of 261215435452616 is 616254534512162.

It is a happy number.

It can be written as a sum of positive squares in only one way, i.e., 232341427562500 + 28874007890116 = 15242750^2 + 5373454^2 .

It is a tau number, because it is divible by the number of its divisors (8).

It is not an unprimeable number, because it can be changed into a prime (261215435452613) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 16325964715781 + ... + 16325964715796.

Almost surely, 2^{261215435452616} is an apocalyptic number.

It is an amenable number.

261215435452616 is a deficient number, since it is larger than the sum of its proper divisors (228563506021054).

261215435452616 is a wasteful number, since it uses less digits than its factorization.

261215435452616 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 32651929431583 (or 32651929431579 counting only the distinct ones).

The product of its digits is 10368000, while the sum is 53.

Adding to 261215435452616 its reverse (616254534512162), we get a palindrome (877469969964778).

The spelling of 261215435452616 in words is "two hundred sixty-one trillion, two hundred fifteen billion, four hundred thirty-five million, four hundred fifty-two thousand, six hundred sixteen".