261383631 has 8 divisors (see below), whose sum is σ = 348601344. Its totient is φ = 174210840.

The previous prime is 261383623. The next prime is 261383693. The reversal of 261383631 is 136383162.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 261383631 - 2³ = 261383623 is a prime.

It is a super-2 number, since 2×261383631² = 136642805109488322, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 261383592 and 261383601.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (261383621) 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 7 ways as a sum of consecutive naturals, for example, 6226 + ... + 23696.

It is an arithmetic number, because the mean of its divisors is an integer number (43575168).

Almost surely, 2^261383631 is an apocalyptic number.

261383631 is a deficient number, since it is larger than the sum of its proper divisors (87217713).

261383631 is a wasteful number, since it uses less digits than its factorization.

261383631 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 22461.

The product of its digits is 15552, while the sum is 33.

The square root of 261383631 is about 16167.3631430731. The cubic root of 261383631 is about 639.3806108751.

The spelling of 261383631 in words is "two hundred sixty-one million, three hundred eighty-three thousand, six hundred thirty-one".