261869400 has 432 divisors, whose sum is σ = 1031808960. Its totient is φ = 59097600.

The previous prime is 261869389. The next prime is 261869407. The reversal of 261869400 is 4968162.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (261869407) by changing a digit.

It is a polite number, since it can be written in 107 ways as a sum of consecutive naturals, for example, 8447385 + ... + 8447415.

Almost surely, 2^261869400 is an apocalyptic number.

261869400 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 261869400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (515904480).

261869400 is an abundant number, since it is smaller than the sum of its proper divisors (769939560).

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

261869400 is a wasteful number, since it uses less digits than its factorization.

261869400 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 104 (or 73 counting only the distinct ones).

The product of its (nonzero) digits is 20736, while the sum is 36.

The square root of 261869400 is about 16182.3793058994. The cubic root of 261869400 is about 639.7764518730.

The spelling of 261869400 in words is "two hundred sixty-one million, eight hundred sixty-nine thousand, four hundred".