121656563 has 24 divisors (see below), whose sum is σ = 150138000. Its totient is φ = 98013888.

The previous prime is 121656551. The next prime is 121656581. The reversal of 121656563 is 365656121.

It is not a de Polignac number, because 121656563 - 2¹² = 121652467 is a prime.

It is a super-3 number, since 3×121656563³ (a number of 25 digits) contains 333 as substring.

It is an alternating number because its digits alternate between odd and even.

It is not an unprimeable number, because it can be changed into a prime (121656533) 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 23 ways as a sum of consecutive naturals, for example, 138281 + ... + 139157.

It is an arithmetic number, because the mean of its divisors is an integer number (6255750).

Almost surely, 2^121656563 is an apocalyptic number.

121656563 is a deficient number, since it is larger than the sum of its proper divisors (28481437).

121656563 is a wasteful number, since it uses less digits than its factorization.

121656563 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1059 (or 1052 counting only the distinct ones).

The product of its digits is 32400, while the sum is 35.

The square root of 121656563 is about 11029.8033980665. The cubic root of 121656563 is about 495.5017366124.

The spelling of 121656563 in words is "one hundred twenty-one million, six hundred fifty-six thousand, five hundred sixty-three".