261858196784 has 20 divisors (see below), whose sum is σ = 507360406320. Its totient is φ = 130926479040.

The previous prime is 261858196771. The next prime is 261858196811. The reversal of 261858196784 is 487691858162.

It is a self number, because there is not a number n which added to its sum of digits gives 261858196784.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 852014 + ... + 1117874.

It is an arithmetic number, because the mean of its divisors is an integer number (25368020316).

Almost surely, 2^261858196784 is an apocalyptic number.

It is an amenable number.

261858196784 is a deficient number, since it is larger than the sum of its proper divisors (245502209536).

261858196784 is a wasteful number, since it uses less digits than its factorization.

261858196784 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 327428 (or 327422 counting only the distinct ones).

The product of its digits is 46448640, while the sum is 65.

The spelling of 261858196784 in words is "two hundred sixty-one billion, eight hundred fifty-eight million, one hundred ninety-six thousand, seven hundred eighty-four".