261631344 has 40 divisors (see below), whose sum is σ = 727873552. Its totient is φ = 80501760.

The previous prime is 261631333. The next prime is 261631361. The reversal of 261631344 is 443136162.

261631344 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a nude number because it is divisible by every one of its digits.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 209017 + ... + 210264.

Almost surely, 2^261631344 is an apocalyptic number.

261631344 is a gapful number since it is divisible by the number (24) formed by its first and last digit.

It is an amenable number.

261631344 is an abundant number, since it is smaller than the sum of its proper divisors (466242208).

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

261631344 is a wasteful number, since it uses less digits than its factorization.

261631344 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 419305 (or 419299 counting only the distinct ones).

The product of its digits is 10368, while the sum is 30.

The square root of 261631344 is about 16175.0222256416. The cubic root of 261631344 is about 639.5825272204.

The spelling of 261631344 in words is "two hundred sixty-one million, six hundred thirty-one thousand, three hundred forty-four".