261089400 has 384 divisors, whose sum is σ = 1012435200. Its totient is φ = 54681600.

The previous prime is 261089377. The next prime is 261089401. The reversal of 261089400 is 4980162.

It is a Harshad number since it is a multiple of its sum of digits (30).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (261089401) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 1458511 + ... + 1458689.

It is an arithmetic number, because the mean of its divisors is an integer number (2636550).

Almost surely, 2^261089400 is an apocalyptic number.

261089400 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 261089400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (506217600).

261089400 is an abundant number, since it is smaller than the sum of its proper divisors (751345800).

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

261089400 is a wasteful number, since it uses less digits than its factorization.

261089400 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 239 (or 230 counting only the distinct ones).

The product of its (nonzero) digits is 3456, while the sum is 30.

The square root of 261089400 is about 16158.2610450506. The cubic root of 261089400 is about 639.1406108555.

The spelling of 261089400 in words is "two hundred sixty-one million, eighty-nine thousand, four hundred".