21521433334 has 8 divisors (see below), whose sum is σ = 32282985168. Its totient is φ = 10760438280.

The previous prime is 21521433319. The next prime is 21521433371. The reversal of 21521433334 is 43333412512.

It is a happy number.

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

It is a junction number, because it is equal to n+sod(n) for n = 21521433296 and 21521433305.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 23242 + ... + 208765.

It is an arithmetic number, because the mean of its divisors is an integer number (4035373146).

Almost surely, 2^21521433334 is an apocalyptic number.

21521433334 is a deficient number, since it is larger than the sum of its proper divisors (10761551834).

21521433334 is a wasteful number, since it uses less digits than its factorization.

21521433334 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 278390.

The product of its digits is 25920, while the sum is 31.

Adding to 21521433334 its reverse (43333412512), we get a palindrome (64854845846).

The spelling of 21521433334 in words is "twenty-one billion, five hundred twenty-one million, four hundred thirty-three thousand, three hundred thirty-four".