21215023353 has 48 divisors (see below), whose sum is σ = 31678395840. Its totient is φ = 13675364352.

The previous prime is 21215023307. The next prime is 21215023369. The reversal of 21215023353 is 35332051212.

It is a happy number.

21215023353 is a `hidden beast` number, since 2 + 121 + 502 + 3 + 35 + 3 = 666.

It is not a de Polignac number, because 21215023353 - 2⁹ = 21215022841 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21215023853) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 11325825 + ... + 11327697.

It is an arithmetic number, because the mean of its divisors is an integer number (659966580).

Almost surely, 2^21215023353 is an apocalyptic number.

It is an amenable number.

21215023353 is a deficient number, since it is larger than the sum of its proper divisors (10463372487).

21215023353 is a wasteful number, since it uses less digits than its factorization.

21215023353 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2278 (or 2275 counting only the distinct ones).

The product of its (nonzero) digits is 5400, while the sum is 27.

Adding to 21215023353 its reverse (35332051212), we get a palindrome (56547074565).

The spelling of 21215023353 in words is "twenty-one billion, two hundred fifteen million, twenty-three thousand, three hundred fifty-three".