261878539104 has 960 divisors, whose sum is σ = 979533789696. Its totient is φ = 66808406016.

The previous prime is 261878539009. The next prime is 261878539127. The reversal of 261878539104 is 401935878162.

261878539104 is a `hidden beast` number, since 2 + 618 + 7 + 8 + 5 + 3 + 9 + 10 + 4 = 666.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 159 ways as a sum of consecutive naturals, for example, 1153649839 + ... + 1153650065.

It is a 1-persistent number, because it is pandigital, but 2⋅261878539104 = 523757078208 is not.

Almost surely, 2^261878539104 is an apocalyptic number.

261878539104 is a gapful number since it is divisible by the number (24) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 261878539104, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (489766894848).

261878539104 is an abundant number, since it is smaller than the sum of its proper divisors (717655250592).

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

261878539104 is a wasteful number, since it uses less digits than its factorization.

261878539104 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 409 (or 392 counting only the distinct ones).

The product of its (nonzero) digits is 2903040, while the sum is 54.

The spelling of 261878539104 in words is "two hundred sixty-one billion, eight hundred seventy-eight million, five hundred thirty-nine thousand, one hundred four".