261826487188 has 24 divisors (see below), whose sum is σ = 524230371392. Its totient is φ = 112087623744.

The previous prime is 261826487177. The next prime is 261826487231. The reversal of 261826487188 is 881784628162.

261826487188 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 5129481 + ... + 5180272.

Almost surely, 2^261826487188 is an apocalyptic number.

261826487188 is a gapful number since it is divisible by the number (28) formed by its first and last digit.

It is an amenable number.

261826487188 is an abundant number, since it is smaller than the sum of its proper divisors (262403884204).

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

261826487188 is a wasteful number, since it uses less digits than its factorization.

261826487188 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10310671 (or 10310669 counting only the distinct ones).

The product of its digits is 16515072, while the sum is 61.

The spelling of 261826487188 in words is "two hundred sixty-one billion, eight hundred twenty-six million, four hundred eighty-seven thousand, one hundred eighty-eight".