261326400 has 84 divisors (see below), whose sum is σ = 857384112. Its totient is φ = 69685760.

The previous prime is 261326393. The next prime is 261326419. The reversal of 261326400 is 4623162.

It is a Harshad number since it is a multiple of its sum of digits (24).

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 22422 + ... + 32021.

Almost surely, 2^261326400 is an apocalyptic number.

261326400 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

261326400 is an abundant number, since it is smaller than the sum of its proper divisors (596057712).

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

261326400 is a wasteful number, since it uses less digits than its factorization.

261326400 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 54468 (or 54453 counting only the distinct ones).

The product of its (nonzero) digits is 1728, while the sum is 24.

The square root of 261326400 is about 16165.5930915015. The cubic root of 261326400 is about 639.3339424812. Note that the first 3 decimals are identical.

Adding to 261326400 its reverse (4623162), we get a palindrome (265949562).

It can be divided in two parts, 261326 and 400, that added together give a triangular number (261726 = T₇₂₃).

The spelling of 261326400 in words is "two hundred sixty-one million, three hundred twenty-six thousand, four hundred".