261626564 has 12 divisors (see below), whose sum is σ = 477753024. Its totient is φ = 125125704.

The previous prime is 261626539. The next prime is 261626569. The reversal of 261626564 is 465626162.

It is not an unprimeable number, because it can be changed into a prime (261626569) by changing a digit.

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 3 ways as a sum of consecutive naturals, for example, 1421792 + ... + 1421975.

It is an arithmetic number, because the mean of its divisors is an integer number (39812752).

Almost surely, 2^261626564 is an apocalyptic number.

It is an amenable number.

261626564 is a deficient number, since it is larger than the sum of its proper divisors (216126460).

261626564 is a wasteful number, since it uses less digits than its factorization.

261626564 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2843794 (or 2843792 counting only the distinct ones).

The product of its digits is 103680, while the sum is 38.

The square root of 261626564 is about 16174.8744662826. The cubic root of 261626564 is about 639.5786321429.

The spelling of 261626564 in words is "two hundred sixty-one million, six hundred twenty-six thousand, five hundred sixty-four".