20121523 has 8 divisors (see below), whose sum is σ = 21517920. Its totient is φ = 18748800.

The previous prime is 20121467. The next prime is 20121533. The reversal of 20121523 is 32512102.

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 20121523 - 2²¹ = 18024371 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 20121497 and 20121506.

It is not an unprimeable number, because it can be changed into a prime (20121533) 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 7 ways as a sum of consecutive naturals, for example, 4143 + ... + 7576.

It is an arithmetic number, because the mean of its divisors is an integer number (2689740).

Almost surely, 2^20121523 is an apocalyptic number.

20121523 is a deficient number, since it is larger than the sum of its proper divisors (1396397).

20121523 is a wasteful number, since it uses less digits than its factorization.

20121523 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11837.

The product of its (nonzero) digits is 120, while the sum is 16.

The square root of 20121523 is about 4485.7020632227. The cubic root of 20121523 is about 271.9904255208.

Adding to 20121523 its reverse (32512102), we get a palindrome (52633625).

The spelling of 20121523 in words is "twenty million, one hundred twenty-one thousand, five hundred twenty-three".