261078787 has 2 divisors, whose sum is σ = 261078788. Its totient is φ = 261078786.

The previous prime is 261078767. The next prime is 261078817. The reversal of 261078787 is 787870162.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-261078787 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (261078737) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 130539393 + 130539394.

It is an arithmetic number, because the mean of its divisors is an integer number (130539394).

Almost surely, 2^261078787 is an apocalyptic number.

261078787 is a deficient number, since it is larger than the sum of its proper divisors (1).

261078787 is an equidigital number, since it uses as much as digits as its factorization.

261078787 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 263424, while the sum is 46.

The square root of 261078787 is about 16157.9326338489. The cubic root of 261078787 is about 639.1319506147.

The spelling of 261078787 in words is "two hundred sixty-one million, seventy-eight thousand, seven hundred eighty-seven".