261568668 has 24 divisors (see below), whose sum is σ = 642449920. Its totient is φ = 82600560.

The previous prime is 261568667. The next prime is 261568721. The reversal of 261568668 is 866865162.

It is a happy number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (261568663) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 573388 + ... + 573843.

Almost surely, 2^261568668 is an apocalyptic number.

It is an amenable number.

261568668 is an abundant number, since it is smaller than the sum of its proper divisors (380881252).

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

261568668 is a wasteful number, since it uses less digits than its factorization.

261568668 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1147257 (or 1147255 counting only the distinct ones).

The product of its digits is 829440, while the sum is 48.

The square root of 261568668 is about 16173.0846779456. The cubic root of 261568668 is about 639.5314506746.

The spelling of 261568668 in words is "two hundred sixty-one million, five hundred sixty-eight thousand, six hundred sixty-eight".