689985766 has 24 divisors (see below), whose sum is σ = 1118130840. Its totient is φ = 319180032.

The previous prime is 689985757. The next prime is 689985767. The reversal of 689985766 is 667589986.

It is a junction number, because it is equal to n+sod(n) for n = 689985698 and 689985707.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (689985767) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 23986 + ... + 44218.

It is an arithmetic number, because the mean of its divisors is an integer number (46588785).

Almost surely, 2^689985766 is an apocalyptic number.

689985766 is a deficient number, since it is larger than the sum of its proper divisors (428145074).

689985766 is a wasteful number, since it uses less digits than its factorization.

689985766 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20328 (or 20311 counting only the distinct ones).

The product of its digits is 39191040, while the sum is 64.

The square root of 689985766 is about 26267.5801321705. The cubic root of 689985766 is about 883.6495158924.

It can be divided in two parts, 6899 and 85766, that added together give a triangular number (92665 = T₄₃₀).

The spelling of 689985766 in words is "six hundred eighty-nine million, nine hundred eighty-five thousand, seven hundred sixty-six".