21123634206446 has 8 divisors (see below), whose sum is σ = 31689044198280. Its totient is φ = 10560619473688.

The previous prime is 21123634206431. The next prime is 21123634206449. The reversal of 21123634206446 is 64460243632112.

It is a happy number.

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

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 21123634206397 and 21123634206406.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21123634206449) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 598792721 + ... + 598827996.

It is an arithmetic number, because the mean of its divisors is an integer number (3961130524785).

Almost surely, 2^{21123634206446} is an apocalyptic number.

21123634206446 is a deficient number, since it is larger than the sum of its proper divisors (10565409991834).

21123634206446 is a wasteful number, since it uses less digits than its factorization.

21123634206446 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1197629538.

The product of its (nonzero) digits is 995328, while the sum is 44.

Adding to 21123634206446 its reverse (64460243632112), we get a palindrome (85583877838558).

The spelling of 21123634206446 in words is "twenty-one trillion, one hundred twenty-three billion, six hundred thirty-four million, two hundred six thousand, four hundred forty-six".