873805781 has 2 divisors, whose sum is σ = 873805782. Its totient is φ = 873805780.

The previous prime is 873805769. The next prime is 873805783. The reversal of 873805781 is 187508378.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 658743556 + 215062225 = 25666^2 + 14665^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-873805781 is a prime.

It is a super-2 number, since 2×873805781² = 1527073085818039922, which contains 22 as substring.

Together with 873805783, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (873805783) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 436902890 + 436902891.

It is an arithmetic number, because the mean of its divisors is an integer number (436902891).

Almost surely, 2^873805781 is an apocalyptic number.

It is an amenable number.

873805781 is a deficient number, since it is larger than the sum of its proper divisors (1).

873805781 is an equidigital number, since it uses as much as digits as its factorization.

873805781 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 376320, while the sum is 47.

The square root of 873805781 is about 29560.2060378476. The cubic root of 873805781 is about 956.0302582727.

The spelling of 873805781 in words is "eight hundred seventy-three million, eight hundred five thousand, seven hundred eighty-one".