70781687 has 2 divisors, whose sum is σ = 70781688. Its totient is φ = 70781686.

The previous prime is 70781639. The next prime is 70781699. The reversal of 70781687 is 78618707.

It is a strong prime.

It is an emirp because it is prime and its reverse (78618707) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 70781687 - 2¹⁰ = 70780663 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (70781987) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 35390843 + 35390844.

It is an arithmetic number, because the mean of its divisors is an integer number (35390844).

Almost surely, 2^70781687 is an apocalyptic number.

70781687 is a deficient number, since it is larger than the sum of its proper divisors (1).

70781687 is an equidigital number, since it uses as much as digits as its factorization.

70781687 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 131712, while the sum is 44.

The square root of 70781687 is about 8413.1853064104. The cubic root of 70781687 is about 413.6569287101.

The spelling of 70781687 in words is "seventy million, seven hundred eighty-one thousand, six hundred eighty-seven".