261615278076 has 48 divisors (see below), whose sum is σ = 616396586400. Its totient is φ = 86354931712.

The previous prime is 261615278063. The next prime is 261615278077. The reversal of 261615278076 is 670872516162.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (261615278077) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1416820 + ... + 1590788.

It is an arithmetic number, because the mean of its divisors is an integer number (12841595550).

Almost surely, 2^261615278076 is an apocalyptic number.

It is an amenable number.

261615278076 is an abundant number, since it is smaller than the sum of its proper divisors (354781308324).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

261615278076 is a wasteful number, since it uses less digits than its factorization.

261615278076 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 175198 (or 175196 counting only the distinct ones).

The product of its (nonzero) digits is 1693440, while the sum is 51.

The spelling of 261615278076 in words is "two hundred sixty-one billion, six hundred fifteen million, two hundred seventy-eight thousand, seventy-six".