121640685 has 16 divisors (see below), whose sum is σ = 195324480. Its totient is φ = 64641920.

The previous prime is 121640677. The next prime is 121640741. The reversal of 121640685 is 586046121.

It is not a de Polignac number, because 121640685 - 2³ = 121640677 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 10215 + ... + 18644.

It is an arithmetic number, because the mean of its divisors is an integer number (12207780).

Almost surely, 2^121640685 is an apocalyptic number.

121640685 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

121640685 is a deficient number, since it is larger than the sum of its proper divisors (73683795).

121640685 is a wasteful number, since it uses less digits than its factorization.

121640685 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 29148.

The product of its (nonzero) digits is 11520, while the sum is 33.

The square root of 121640685 is about 11029.0835974708. The cubic root of 121640685 is about 495.4801788800.

The spelling of 121640685 in words is "one hundred twenty-one million, six hundred forty thousand, six hundred eighty-five".