261530431 has 8 divisors (see below), whose sum is σ = 283669344. Its totient is φ = 240142080.

The previous prime is 261530411. The next prime is 261530441. The reversal of 261530431 is 134035162.

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

It is a cyclic number.

It is not a de Polignac number, because 261530431 - 2¹¹ = 261528383 is a prime.

It is a super-2 number, since 2×261530431² = 136796332678091522, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 261530396 and 261530405.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (261530411) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 186915 + ... + 188308.

It is an arithmetic number, because the mean of its divisors is an integer number (35458668).

Almost surely, 2^261530431 is an apocalyptic number.

261530431 is a deficient number, since it is larger than the sum of its proper divisors (22138913).

261530431 is a wasteful number, since it uses less digits than its factorization.

261530431 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 375281.

The product of its (nonzero) digits is 2160, while the sum is 25.

The square root of 261530431 is about 16171.9025164017. The cubic root of 261530431 is about 639.5002861931.

Adding to 261530431 its reverse (134035162), we get a palindrome (395565593).

The spelling of 261530431 in words is "two hundred sixty-one million, five hundred thirty thousand, four hundred thirty-one".