261631337 has 16 divisors (see below), whose sum is σ = 288585024. Its totient is φ = 235224000.

The previous prime is 261631333. The next prime is 261631361. The reversal of 261631337 is 733136162.

It is not a de Polignac number, because 261631337 - 2² = 261631333 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (261631333) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 658823 + ... + 659219.

It is an arithmetic number, because the mean of its divisors is an integer number (18036564).

Almost surely, 2^261631337 is an apocalyptic number.

It is an amenable number.

261631337 is a deficient number, since it is larger than the sum of its proper divisors (26953687).

261631337 is a wasteful number, since it uses less digits than its factorization.

261631337 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 920.

The product of its digits is 13608, while the sum is 32.

The square root of 261631337 is about 16175.0220092586. The cubic root of 261631337 is about 639.5825215163.

Adding to 261631337 its reverse (733136162), we get a palindrome (994767499).

The spelling of 261631337 in words is "two hundred sixty-one million, six hundred thirty-one thousand, three hundred thirty-seven".