261151664 has 20 divisors (see below), whose sum is σ = 506328456. Its totient is φ = 130486272.

The previous prime is 261151663. The next prime is 261151679. The reversal of 261151664 is 466151162.

It is a self number, because there is not a number n which added to its sum of digits gives 261151664.

It is not an unprimeable number, because it can be changed into a prime (261151663) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 22832 + ... + 32304.

Almost surely, 2^261151664 is an apocalyptic number.

It is an amenable number.

261151664 is a deficient number, since it is larger than the sum of its proper divisors (245176792).

261151664 is a wasteful number, since it uses less digits than its factorization.

261151664 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11204 (or 11198 counting only the distinct ones).

The product of its digits is 8640, while the sum is 32.

The square root of 261151664 is about 16160.1876226732. The cubic root of 261151664 is about 639.1914137452.

The spelling of 261151664 in words is "two hundred sixty-one million, one hundred fifty-one thousand, six hundred sixty-four".