685867870 has 16 divisors (see below), whose sum is σ = 1274387328. Its totient is φ = 265497120.

The previous prime is 685867849. The next prime is 685867879. The reversal of 685867870 is 78768586.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (685867879) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1105929 + ... + 1106548.

It is an arithmetic number, because the mean of its divisors is an integer number (79649208).

Almost surely, 2^685867870 is an apocalyptic number.

685867870 is a deficient number, since it is larger than the sum of its proper divisors (588519458).

685867870 is a wasteful number, since it uses less digits than its factorization.

685867870 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2212515.

The product of its (nonzero) digits is 4515840, while the sum is 55.

The square root of 685867870 is about 26189.0792125267. The cubic root of 685867870 is about 881.8881076959. Note that the first 3 decimals are identical.

The spelling of 685867870 in words is "six hundred eighty-five million, eight hundred sixty-seven thousand, eight hundred seventy".