810866805 has 32 divisors (see below), whose sum is σ = 1496352000. Its totient is φ = 367276032.

The previous prime is 810866801. The next prime is 810866827. The reversal of 810866805 is 508668018.

It is not a de Polignac number, because 810866805 - 2² = 810866801 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (810866801) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 23980 + ... + 46869.

It is an arithmetic number, because the mean of its divisors is an integer number (46761000).

Almost surely, 2^810866805 is an apocalyptic number.

It is an amenable number.

810866805 is a deficient number, since it is larger than the sum of its proper divisors (685485195).

810866805 is a wasteful number, since it uses less digits than its factorization.

810866805 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 70973.

The product of its (nonzero) digits is 92160, while the sum is 42.

The square root of 810866805 is about 28475.7230812494. The cubic root of 810866805 is about 932.5021474026.

The spelling of 810866805 in words is "eight hundred ten million, eight hundred sixty-six thousand, eight hundred five".