121569421 has 16 divisors (see below), whose sum is σ = 132652800. Its totient is φ = 111057408.

The previous prime is 121569419. The next prime is 121569433. The reversal of 121569421 is 124965121.

It is a cyclic number.

It is not a de Polignac number, because 121569421 - 2¹ = 121569419 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 (121569451) 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 in 15 ways as a sum of consecutive naturals, for example, 63760 + ... + 65638.

It is an arithmetic number, because the mean of its divisors is an integer number (8290800).

Almost surely, 2^121569421 is an apocalyptic number.

It is an amenable number.

121569421 is a deficient number, since it is larger than the sum of its proper divisors (11083379).

121569421 is a wasteful number, since it uses less digits than its factorization.

121569421 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2028.

The product of its digits is 4320, while the sum is 31.

The square root of 121569421 is about 11025.8523933526. The cubic root of 121569421 is about 495.3833998645.

The spelling of 121569421 in words is "one hundred twenty-one million, five hundred sixty-nine thousand, four hundred twenty-one".