121638395 has 4 divisors (see below), whose sum is σ = 145966080. Its totient is φ = 97310712.

The previous prime is 121638379. The next prime is 121638401. The reversal of 121638395 is 593836121.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 593836121 = 59 ⋅10065019.

It is a cyclic number.

It is not a de Polignac number, because 121638395 - 2⁴ = 121638379 is a prime.

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, 12163835 + ... + 12163844.

It is an arithmetic number, because the mean of its divisors is an integer number (36491520).

Almost surely, 2^121638395 is an apocalyptic number.

121638395 is a deficient number, since it is larger than the sum of its proper divisors (24327685).

121638395 is an equidigital number, since it uses as much as digits as its factorization.

121638395 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 24327684.

The product of its digits is 38880, while the sum is 38.

The square root of 121638395 is about 11028.9797805599. The cubic root of 121638395 is about 495.4770695675.

The spelling of 121638395 in words is "one hundred twenty-one million, six hundred thirty-eight thousand, three hundred ninety-five".