21548258221 has 8 divisors (see below), whose sum is σ = 24647765184. Its totient is φ = 18454047360.

The previous prime is 21548258201. The next prime is 21548258231. The reversal of 21548258221 is 12285284512.

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

It is not a de Polignac number, because 21548258221 - 2²³ = 21539869613 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21548258201) 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, 1315300 + ... + 1331581.

It is an arithmetic number, because the mean of its divisors is an integer number (3080970648).

Almost surely, 2^21548258221 is an apocalyptic number.

It is an amenable number.

21548258221 is a deficient number, since it is larger than the sum of its proper divisors (3099506963).

21548258221 is a wasteful number, since it uses less digits than its factorization.

21548258221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2648051.

The product of its digits is 102400, while the sum is 40.

The spelling of 21548258221 in words is "twenty-one billion, five hundred forty-eight million, two hundred fifty-eight thousand, two hundred twenty-one".