261165630 has 32 divisors (see below), whose sum is σ = 683779968. Its totient is φ = 63312800.

The previous prime is 261165629. The next prime is 261165631. The reversal of 261165630 is 36561162.

261165630 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is an interprime number because it is at equal distance from previous prime (261165629) and next prime (261165631).

It is a Harshad number since it is a multiple of its sum of digits (30).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (261165631) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 395376 + ... + 396035.

It is an arithmetic number, because the mean of its divisors is an integer number (21368124).

Almost surely, 2^261165630 is an apocalyptic number.

261165630 is an abundant number, since it is smaller than the sum of its proper divisors (422614338).

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

261165630 is a wasteful number, since it uses less digits than its factorization.

261165630 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 791432.

The product of its (nonzero) digits is 6480, while the sum is 30.

The square root of 261165630 is about 16160.6197282159. The cubic root of 261165630 is about 639.2028078754.

The spelling of 261165630 in words is "two hundred sixty-one million, one hundred sixty-five thousand, six hundred thirty".