261315400 has 48 divisors (see below), whose sum is σ = 613286640. Its totient is φ = 103540800.

The previous prime is 261315391. The next prime is 261315409. The reversal of 261315400 is 4513162.

It is an interprime number because it is at equal distance from previous prime (261315391) and next prime (261315409).

It is a hoax number, since the sum of its digits (22) coincides with the sum of the digits of its distinct prime factors.

It is not an unprimeable number, because it can be changed into a prime (261315409) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 15295 + ... + 27505.

It is an arithmetic number, because the mean of its divisors is an integer number (12776805).

Almost surely, 2^261315400 is an apocalyptic number.

261315400 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 261315400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (306643320).

261315400 is an abundant number, since it is smaller than the sum of its proper divisors (351971240).

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

261315400 is a wasteful number, since it uses less digits than its factorization.

261315400 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12334 (or 12325 counting only the distinct ones).

The product of its (nonzero) digits is 720, while the sum is 22.

The square root of 261315400 is about 16165.2528591420. The cubic root of 261315400 is about 639.3249718707.

Adding to 261315400 its reverse (4513162), we get a palindrome (265828562).

The spelling of 261315400 in words is "two hundred sixty-one million, three hundred fifteen thousand, four hundred".