261421660425255 has 64 divisors (see below), whose sum is σ = 460011299586048. Its totient is φ = 125719390863360.

The previous prime is 261421660425239. The next prime is 261421660425337. The reversal of 261421660425255 is 552524066124162.

It is not a de Polignac number, because 261421660425255 - 2⁴ = 261421660425239 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 261421660425198 and 261421660425207.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 79633639 + ... + 82851431.

It is an arithmetic number, because the mean of its divisors is an integer number (7187676556032).

Almost surely, 2^{261421660425255} is an apocalyptic number.

261421660425255 is a deficient number, since it is larger than the sum of its proper divisors (198589639160793).

261421660425255 is a wasteful number, since it uses less digits than its factorization.

261421660425255 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3221816.

The product of its (nonzero) digits is 6912000, while the sum is 51.

The spelling of 261421660425255 in words is "two hundred sixty-one trillion, four hundred twenty-one billion, six hundred sixty million, four hundred twenty-five thousand, two hundred fifty-five".