1261335687 has 8 divisors (see below), whose sum is σ = 1681945200. Its totient is φ = 840808320.

The previous prime is 1261335671. The next prime is 1261335703. The reversal of 1261335687 is 7865331621.

1261335687 is digitally balanced in base 4, 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 (1261335671) and next prime (1261335703).

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 1261335687 - 2⁴ = 1261335671 is a prime.

It is a Smith number, since the sum of its digits (42) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1261335637) 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, 47439 + ... + 69087.

It is an arithmetic number, because the mean of its divisors is an integer number (210243150).

Almost surely, 2^1261335687 is an apocalyptic number.

1261335687 is a deficient number, since it is larger than the sum of its proper divisors (420609513).

1261335687 is a wasteful number, since it uses less digits than its factorization.

1261335687 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 41073.

The product of its digits is 181440, while the sum is 42.

The square root of 1261335687 is about 35515.2880742927. The cubic root of 1261335687 is about 1080.4638174126.

The spelling of 1261335687 in words is "one billion, two hundred sixty-one million, three hundred thirty-five thousand, six hundred eighty-seven".