261854735040 has 896 divisors, whose sum is σ = 1022489395200. Its totient is φ = 62790266880.

The previous prime is 261854735033. The next prime is 261854735083. The reversal of 261854735040 is 40537458162.

261854735040 is a `hidden beast` number, since 2 + 6 + 18 + 547 + 3 + 50 + 40 = 666.

261854735040 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a Harshad number since it is a multiple of its sum of digits (45).

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 127 ways as a sum of consecutive naturals, for example, 841976485 + ... + 841976795.

It is an arithmetic number, because the mean of its divisors is an integer number (1141171200).

Almost surely, 2^261854735040 is an apocalyptic number.

261854735040 is a gapful number since it is divisible by the number (20) 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 261854735040, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (511244697600).

261854735040 is an abundant number, since it is smaller than the sum of its proper divisors (760634660160).

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

261854735040 is a wasteful number, since it uses less digits than its factorization.

261854735040 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 602 (or 586 counting only the distinct ones).

The product of its (nonzero) digits is 806400, while the sum is 45.

The spelling of 261854735040 in words is "two hundred sixty-one billion, eight hundred fifty-four million, seven hundred thirty-five thousand, forty".