261723571200 has 2640 divisors, whose sum is σ = 1272754510720. Its totient is φ = 51597803520.

The previous prime is 261723571121. The next prime is 261723571223. The reversal of 261723571200 is 2175327162.

261723571200 is a `hidden beast` number, since 2 + 61 + 7 + 2 + 3 + 571 + 20 + 0 = 666.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is an unprimeable number.

It is a polite number, since it can be written in 239 ways as a sum of consecutive naturals, for example, 3585254364 + ... + 3585254436.

Almost surely, 2^261723571200 is an apocalyptic number.

261723571200 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 261723571200, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (636377255360).

261723571200 is an abundant number, since it is smaller than the sum of its proper divisors (1011030939520).

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

261723571200 is a wasteful number, since it uses less digits than its factorization.

261723571200 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 154 (or 122 counting only the distinct ones).

The product of its (nonzero) digits is 35280, while the sum is 36.

Adding to 261723571200 its reverse (2175327162), we get a palindrome (263898898362).

The spelling of 261723571200 in words is "two hundred sixty-one billion, seven hundred twenty-three million, five hundred seventy-one thousand, two hundred".