261776730 has 32 divisors (see below), whose sum is σ = 628689600. Its totient is φ = 69759872.

The previous prime is 261776729. The next prime is 261776743. The reversal of 261776730 is 37677162.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 86686 + ... + 89654.

It is an arithmetic number, because the mean of its divisors is an integer number (19646550).

Almost surely, 2^261776730 is an apocalyptic number.

261776730 is an abundant number, since it is smaller than the sum of its proper divisors (366912870).

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

261776730 is a wasteful number, since it uses less digits than its factorization.

261776730 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5918.

The product of its (nonzero) digits is 74088, while the sum is 39.

The square root of 261776730 is about 16179.5157529513. The cubic root of 261776730 is about 639.7009752184.

The spelling of 261776730 in words is "two hundred sixty-one million, seven hundred seventy-six thousand, seven hundred thirty".