261534634 has 16 divisors (see below), whose sum is σ = 400860000. Its totient is φ = 127941264.

The previous prime is 261534629. The next prime is 261534659. The reversal of 261534634 is 436435162.

It is a self number, because there is not a number n which added to its sum of digits gives 261534634.

It is an unprimeable number.

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, 13417 + ... + 26515.

It is an arithmetic number, because the mean of its divisors is an integer number (25053750).

Almost surely, 2^261534634 is an apocalyptic number.

261534634 is a deficient number, since it is larger than the sum of its proper divisors (139325366).

261534634 is a wasteful number, since it uses less digits than its factorization.

261534634 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13317.

The product of its digits is 51840, while the sum is 34.

The square root of 261534634 is about 16172.0324634846. The cubic root of 261534634 is about 639.5037119325.

Adding to 261534634 its reverse (436435162), we get a palindrome (697969796).

It can be divided in two parts, 2615 and 34634, that added together give a square (37249 = 193²).

The spelling of 261534634 in words is "two hundred sixty-one million, five hundred thirty-four thousand, six hundred thirty-four".