21353933418 has 16 divisors (see below), whose sum is σ = 42718811520. Its totient is φ = 7116153696.

The previous prime is 21353933417. The next prime is 21353933431. The reversal of 21353933418 is 81433935312.

It is a self number, because there is not a number n which added to its sum of digits gives 21353933418.

It is not an unprimeable number, because it can be changed into a prime (21353933417) 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, 430555 + ... + 477582.

It is an arithmetic number, because the mean of its divisors is an integer number (2669925720).

Almost surely, 2^21353933418 is an apocalyptic number.

21353933418 is an abundant number, since it is smaller than the sum of its proper divisors (21364878102).

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

21353933418 is a wasteful number, since it uses less digits than its factorization.

21353933418 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 912061.

The product of its digits is 233280, while the sum is 42.

The spelling of 21353933418 in words is "twenty-one billion, three hundred fifty-three million, nine hundred thirty-three thousand, four hundred eighteen".