21213244434 has 16 divisors (see below), whose sum is σ = 42527269440. Its totient is φ = 7054284720.

The previous prime is 21213244433. The next prime is 21213244489. The reversal of 21213244434 is 43444231212.

It is not an unprimeable number, because it can be changed into a prime (21213244433) 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, 4196454 + ... + 4201505.

It is an arithmetic number, because the mean of its divisors is an integer number (2657954340).

Almost surely, 2^21213244434 is an apocalyptic number.

21213244434 is an abundant number, since it is smaller than the sum of its proper divisors (21314025006).

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

21213244434 is a wasteful number, since it uses less digits than its factorization.

21213244434 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8398385.

The product of its digits is 18432, while the sum is 30.

Adding to 21213244434 its reverse (43444231212), we get a palindrome (64657475646).

The spelling of 21213244434 in words is "twenty-one billion, two hundred thirteen million, two hundred forty-four thousand, four hundred thirty-four".