121898640409 has 16 divisors (see below), whose sum is σ = 152571968640. Its totient is φ = 94812572160.

The previous prime is 121898640379. The next prime is 121898640439. The reversal of 121898640409 is 904046898121.

It is an interprime number because it is at equal distance from previous prime (121898640379) and next prime (121898640439).

It is a cyclic number.

It is not a de Polignac number, because 121898640409 - 2⁹ = 121898639897 is a prime.

It is not an unprimeable number, because it can be changed into a prime (121898640439) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 11346712 + ... + 11357449.

It is an arithmetic number, because the mean of its divisors is an integer number (9535748040).

Almost surely, 2^121898640409 is an apocalyptic number.

It is an amenable number.

121898640409 is a deficient number, since it is larger than the sum of its proper divisors (30673328231).

121898640409 is a wasteful number, since it uses less digits than its factorization.

121898640409 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 22704240.

The product of its (nonzero) digits is 995328, while the sum is 52.

The spelling of 121898640409 in words is "one hundred twenty-one billion, eight hundred ninety-eight million, six hundred forty thousand, four hundred nine".