21216223650254 has 4 divisors (see below), whose sum is σ = 31824335475384. Its totient is φ = 10608111825126.

The previous prime is 21216223650187. The next prime is 21216223650299. The reversal of 21216223650254 is 45205632261212.

It is a semiprime because it is the product of two primes.

It is a super-2 number, since 2×21216223650254² (a number of 27 digits) contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5304055912562 + ... + 5304055912565.

It is an arithmetic number, because the mean of its divisors is an integer number (7956083868846).

Almost surely, 2^{21216223650254} is an apocalyptic number.

21216223650254 is a deficient number, since it is larger than the sum of its proper divisors (10608111825130).

21216223650254 is a wasteful number, since it uses less digits than its factorization.

21216223650254 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10608111825129.

The product of its (nonzero) digits is 345600, while the sum is 41.

The spelling of 21216223650254 in words is "twenty-one trillion, two hundred sixteen billion, two hundred twenty-three million, six hundred fifty thousand, two hundred fifty-four".