121899908081 has 4 divisors (see below), whose sum is σ = 139314180672. Its totient is φ = 104485635492.

The previous prime is 121899908029. The next prime is 121899908099. The reversal of 121899908081 is 180809998121.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 121899908081 - 2¹⁴ = 121899891697 is a prime.

It is a super-2 number, since 2×121899908081² (a number of 23 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (121899908381) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 8707136285 + ... + 8707136298.

It is an arithmetic number, because the mean of its divisors is an integer number (34828545168).

Almost surely, 2^121899908081 is an apocalyptic number.

It is an amenable number.

121899908081 is a deficient number, since it is larger than the sum of its proper divisors (17414272591).

121899908081 is an equidigital number, since it uses as much as digits as its factorization.

121899908081 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 17414272590.

The product of its (nonzero) digits is 746496, while the sum is 56.

The spelling of 121899908081 in words is "one hundred twenty-one billion, eight hundred ninety-nine million, nine hundred eight thousand, eighty-one".