261436487120 has 40 divisors (see below), whose sum is σ = 628799832360. Its totient is φ = 100968573440.

The previous prime is 261436487119. The next prime is 261436487131. The reversal of 261436487120 is 21784634162.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 8008818064 + 253427669056 = 89492^2 + 503416^2 .

It is a tau number, because it is divible by the number of its divisors (40).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 56341751 + ... + 56346390.

It is an arithmetic number, because the mean of its divisors is an integer number (15719995809).

Almost surely, 2^261436487120 is an apocalyptic number.

261436487120 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

261436487120 is an abundant number, since it is smaller than the sum of its proper divisors (367363345240).

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

261436487120 is a wasteful number, since it uses less digits than its factorization.

261436487120 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 112688183 (or 112688177 counting only the distinct ones).

The product of its (nonzero) digits is 387072, while the sum is 44.

The spelling of 261436487120 in words is "two hundred sixty-one billion, four hundred thirty-six million, four hundred eighty-seven thousand, one hundred twenty".