121813904 has 10 divisors (see below), whose sum is σ = 236014470. Its totient is φ = 60906944.

The previous prime is 121813903. The next prime is 121813927. The reversal of 121813904 is 409318121.

It can be written as a sum of positive squares in only one way, i.e., 69222400 + 52591504 = 8320^2 + 7252^2 .

It is a super-3 number, since 3×121813904³ (a number of 25 digits) contains 333 as substring.

It is not an unprimeable number, because it can be changed into a prime (121813903) by changing a digit.

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 as a sum of consecutive naturals, namely, 3806669 + ... + 3806700.

It is an arithmetic number, because the mean of its divisors is an integer number (23601447).

Almost surely, 2^121813904 is an apocalyptic number.

It is an amenable number.

121813904 is a deficient number, since it is larger than the sum of its proper divisors (114200566).

121813904 is an equidigital number, since it uses as much as digits as its factorization.

121813904 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7613377 (or 7613371 counting only the distinct ones).

The product of its (nonzero) digits is 1728, while the sum is 29.

The square root of 121813904 is about 11036.9336321281. The cubic root of 121813904 is about 495.7152588717.

The spelling of 121813904 in words is "one hundred twenty-one million, eight hundred thirteen thousand, nine hundred four".