261040626 has 96 divisors (see below), whose sum is σ = 711180288. Its totient is φ = 67223520.

The previous prime is 261040621. The next prime is 261040657. The reversal of 261040626 is 626040162.

It is a happy number.

261040626 is a `hidden beast` number, since 2 + 610 + 40 + 6 + 2 + 6 = 666.

It is a self number, because there is not a number n which added to its sum of digits gives 261040626.

It is not an unprimeable number, because it can be changed into a prime (261040621) 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 47 ways as a sum of consecutive naturals, for example, 175281 + ... + 176763.

It is an arithmetic number, because the mean of its divisors is an integer number (7408128).

Almost surely, 2^261040626 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 261040626, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (355590144).

261040626 is an abundant number, since it is smaller than the sum of its proper divisors (450139662).

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

261040626 is a wasteful number, since it uses less digits than its factorization.

261040626 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1636 (or 1633 counting only the distinct ones).

The product of its (nonzero) digits is 3456, while the sum is 27.

The square root of 261040626 is about 16156.7517156141. The cubic root of 261040626 is about 639.1008091816.

Adding to 261040626 its reverse (626040162), we get a palindrome (887080788).

The spelling of 261040626 in words is "two hundred sixty-one million, forty thousand, six hundred twenty-six".