121643564 has 24 divisors (see below), whose sum is σ = 245525280. Its totient is φ = 51653376.

The previous prime is 121643539. The next prime is 121643569. The reversal of 121643564 is 465346121.

It is a self number, because there is not a number n which added to its sum of digits gives 121643564.

It is not an unprimeable number, because it can be changed into a prime (121643569) 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, 16877 + ... + 22980.

It is an arithmetic number, because the mean of its divisors is an integer number (10230220).

Almost surely, 2^121643564 is an apocalyptic number.

121643564 is a gapful number since it is divisible by the number (14) formed by its first and last digit.

It is an amenable number.

121643564 is an abundant number, since it is smaller than the sum of its proper divisors (123881716).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

121643564 is a wasteful number, since it uses less digits than its factorization.

121643564 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 39977 (or 39975 counting only the distinct ones).

The product of its digits is 17280, while the sum is 32.

The square root of 121643564 is about 11029.2141152486. The cubic root of 121643564 is about 495.4840878687.

Adding to 121643564 its reverse (465346121), we get a palindrome (586989685).

The spelling of 121643564 in words is "one hundred twenty-one million, six hundred forty-three thousand, five hundred sixty-four".