261791424 has 126 divisors (see below), whose sum is σ = 792579060. Its totient is φ = 82605312.

The previous prime is 261791423. The next prime is 261791429. The reversal of 261791424 is 424197162.

It is a happy number.

261791424 is a `hidden beast` number, since 2 + 617 + 9 + 14 + 24 = 666.

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

It is not an unprimeable number, because it can be changed into a prime (261791423) by changing a digit.

It is a polite number, since it can be written in 17 ways as a sum of consecutive naturals, for example, 207307 + ... + 208565.

It is an arithmetic number, because the mean of its divisors is an integer number (6290310).

Almost surely, 2^261791424 is an apocalyptic number.

261791424 is a gapful number since it is divisible by the number (24) 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 261791424, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (396289530).

261791424 is an abundant number, since it is smaller than the sum of its proper divisors (530787636).

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

261791424 is a wasteful number, since it uses less digits than its factorization.

261791424 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1315 (or 1283 counting only the distinct ones).

The product of its digits is 24192, while the sum is 36.

The square root of 261791424 is about 16179.9698392797. The cubic root of 261791424 is about 639.7129441843.

The spelling of 261791424 in words is "two hundred sixty-one million, seven hundred ninety-one thousand, four hundred twenty-four".