785871666 has 64 divisors (see below), whose sum is σ = 1773907200. Its totient is φ = 257862528.

The previous prime is 785871643. The next prime is 785871677. The reversal of 785871666 is 666178587.

It is a Harshad number since it is a multiple of its sum of digits (54).

Its product of digits (3386880) is a multiple of the sum of its prime factors (960).

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 1273390 + ... + 1274006.

It is an arithmetic number, because the mean of its divisors is an integer number (27717300).

Almost surely, 2^785871666 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 785871666, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (886953600).

785871666 is an abundant number, since it is smaller than the sum of its proper divisors (988035534).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

785871666 is a wasteful number, since it uses less digits than its factorization.

785871666 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 960 (or 954 counting only the distinct ones).

The product of its digits is 3386880, while the sum is 54.

The square root of 785871666 is about 28033.4026832277. The cubic root of 785871666 is about 922.8204505065.

It can be divided in two parts, 7858 and 71666, that added together give a square (79524 = 282²).

The spelling of 785871666 in words is "seven hundred eighty-five million, eight hundred seventy-one thousand, six hundred sixty-six".