261220520120 has 32 divisors (see below), whose sum is σ = 671709909600. Its totient is φ = 89561321088.

The previous prime is 261220520117. The next prime is 261220520161. The reversal of 261220520120 is 21025022162.

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, 466464935 + ... + 466465494.

It is an arithmetic number, because the mean of its divisors is an integer number (20990934675).

Almost surely, 2^261220520120 is an apocalyptic number.

261220520120 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

261220520120 is an abundant number, since it is smaller than the sum of its proper divisors (410489389480).

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

261220520120 is a wasteful number, since it uses less digits than its factorization.

261220520120 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 932930447 (or 932930443 counting only the distinct ones).

The product of its (nonzero) digits is 960, while the sum is 23.

Adding to 261220520120 its reverse (21025022162), we get a palindrome (282245542282).

The spelling of 261220520120 in words is "two hundred sixty-one billion, two hundred twenty million, five hundred twenty thousand, one hundred twenty".