121636421 has 8 divisors (see below), whose sum is σ = 123379200. Its totient is φ = 119904400.

The previous prime is 121636399. The next prime is 121636429. The reversal of 121636421 is 124636121.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 121636421 - 2¹⁸ = 121374277 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (121636429) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 21620 + ... + 26658.

It is an arithmetic number, because the mean of its divisors is an integer number (15422400).

Almost surely, 2^121636421 is an apocalyptic number.

It is an amenable number.

121636421 is a deficient number, since it is larger than the sum of its proper divisors (1742779).

121636421 is a wasteful number, since it uses less digits than its factorization.

121636421 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5379.

The product of its digits is 1728, while the sum is 26.

The square root of 121636421 is about 11028.8902886918. The cubic root of 121636421 is about 495.4743892815.

The spelling of 121636421 in words is "one hundred twenty-one million, six hundred thirty-six thousand, four hundred twenty-one".