121685618 has 8 divisors (see below), whose sum is σ = 183753900. Its totient is φ = 60434320.

The previous prime is 121685593. The next prime is 121685623. The reversal of 121685618 is 816586121.

It can be written as a sum of positive squares in 2 ways, for example, as 99341089 + 22344529 = 9967^2 + 4727^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 203873 + ... + 204468.

Almost surely, 2^121685618 is an apocalyptic number.

121685618 is a deficient number, since it is larger than the sum of its proper divisors (62068282).

121685618 is a wasteful number, since it uses less digits than its factorization.

121685618 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 408492.

The product of its digits is 23040, while the sum is 38.

The square root of 121685618 is about 11031.1204326668. The cubic root of 121685618 is about 495.5411800440.

It can be divided in two parts, 12168 and 5618, that multiplied together give a square (68359824 = 8268²).

The spelling of 121685618 in words is "one hundred twenty-one million, six hundred eighty-five thousand, six hundred eighteen".