261200000 has 96 divisors (see below), whose sum is σ = 651403620. Its totient is φ = 104320000.

The previous prime is 261199999. The next prime is 261200003. The reversal of 261200000 is 2162.

It can be written as a sum of positive squares in 6 ways, for example, as 59105344 + 202094656 = 7688^2 + 14216^2 .

It is not an unprimeable number, because it can be changed into a prime (261200003) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 399674 + ... + 400326.

Almost surely, 2^261200000 is an apocalyptic number.

261200000 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 261200000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (325701810).

261200000 is an abundant number, since it is smaller than the sum of its proper divisors (390203620).

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

261200000 is an frugal number, since it uses more digits than its factorization.

261200000 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 692 (or 660 counting only the distinct ones).

The product of its (nonzero) digits is 24, while the sum is 11.

The square root of 261200000 is about 16161.6830806695. The cubic root of 261200000 is about 639.2308468340.

Adding to 261200000 its reverse (2162), we get a palindrome (261202162).

The spelling of 261200000 in words is "two hundred sixty-one million, two hundred thousand".