21215023354 has 16 divisors (see below), whose sum is σ = 37255651776. Its totient is φ = 8870392800.

The previous prime is 21215023307. The next prime is 21215023369. The reversal of 21215023354 is 45332051212.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 18479412 + ... + 18480559.

It is an arithmetic number, because the mean of its divisors is an integer number (2328478236).

Almost surely, 2^21215023354 is an apocalyptic number.

21215023354 is a deficient number, since it is larger than the sum of its proper divisors (16040628422).

21215023354 is a wasteful number, since it uses less digits than its factorization.

21215023354 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 36960021.

The product of its (nonzero) digits is 7200, while the sum is 28.

Adding to 21215023354 its reverse (45332051212), we get a palindrome (66547074566).

The spelling of 21215023354 in words is "twenty-one billion, two hundred fifteen million, twenty-three thousand, three hundred fifty-four".