261258280643400 has 192 divisors, whose sum is σ = 827199611193600. Its totient is φ = 68181034076160.

The previous prime is 261258280643363. The next prime is 261258280643401. The reversal of 261258280643400 is 4346082852162.

It is not an unprimeable number, because it can be changed into a prime (261258280643401) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 353625586 + ... + 354363614.

It is an arithmetic number, because the mean of its divisors is an integer number (4308331308300).

Almost surely, 2^{261258280643400} is an apocalyptic number.

261258280643400 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 261258280643400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (413599805596800).

261258280643400 is an abundant number, since it is smaller than the sum of its proper divisors (565941330550200).

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

261258280643400 is a wasteful number, since it uses less digits than its factorization.

261258280643400 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 750648 (or 750639 counting only the distinct ones).

The product of its (nonzero) digits is 4423680, while the sum is 51.

The spelling of 261258280643400 in words is "two hundred sixty-one trillion, two hundred fifty-eight billion, two hundred eighty million, six hundred forty-three thousand, four hundred".