261620534 has 16 divisors (see below), whose sum is σ = 448700928. Its totient is φ = 112070952.

The previous prime is 261620509. The next prime is 261620551. The reversal of 261620534 is 435026162.

It is a junction number, because it is equal to n+sod(n) for n = 261620497 and 261620506.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 52307 + ... + 57089.

It is an arithmetic number, because the mean of its divisors is an integer number (28043808).

Almost surely, 2^261620534 is an apocalyptic number.

261620534 is a deficient number, since it is larger than the sum of its proper divisors (187080394).

261620534 is a wasteful number, since it uses less digits than its factorization.

261620534 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8699.

The product of its (nonzero) digits is 8640, while the sum is 29.

The square root of 261620534 is about 16174.6880649983. The cubic root of 261620534 is about 639.5737184104.

Adding to 261620534 its reverse (435026162), we get a palindrome (696646696).

The spelling of 261620534 in words is "two hundred sixty-one million, six hundred twenty thousand, five hundred thirty-four".