261243924 has 24 divisors (see below), whose sum is σ = 615269088. Its totient is φ = 86267040.

The previous prime is 261243889. The next prime is 261243929. The reversal of 261243924 is 429342162.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (261243929) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 100447 + ... + 103014.

It is an arithmetic number, because the mean of its divisors is an integer number (25636212).

Almost surely, 2^261243924 is an apocalyptic number.

It is an amenable number.

261243924 is an abundant number, since it is smaller than the sum of its proper divisors (354025164).

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

261243924 is a wasteful number, since it uses less digits than its factorization.

261243924 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 203575 (or 203573 counting only the distinct ones).

The product of its digits is 20736, while the sum is 33.

The square root of 261243924 is about 16163.0419166690. The cubic root of 261243924 is about 639.2666763414.

The spelling of 261243924 in words is "two hundred sixty-one million, two hundred forty-three thousand, nine hundred twenty-four".