21375072106221 has 8 divisors (see below), whose sum is σ = 28708126041024. Its totient is φ = 14146033121120.

The previous prime is 21375072106207. The next prime is 21375072106229. The reversal of 21375072106221 is 12260127057312.

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

It is a cyclic number.

It is not a de Polignac number, because 21375072106221 - 2¹⁴ = 21375072089837 is a prime.

It is a super-2 number, since 2×21375072106221² (a number of 27 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 21375072106221.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21375072106229) 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, 26003736945 + ... + 26003737766.

It is an arithmetic number, because the mean of its divisors is an integer number (3588515755128).

Almost surely, 2^{21375072106221} is an apocalyptic number.

It is an amenable number.

21375072106221 is a deficient number, since it is larger than the sum of its proper divisors (7333053934803).

21375072106221 is a wasteful number, since it uses less digits than its factorization.

21375072106221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 52007474851.

The product of its (nonzero) digits is 70560, while the sum is 39.

The spelling of 21375072106221 in words is "twenty-one trillion, three hundred seventy-five billion, seventy-two million, one hundred six thousand, two hundred twenty-one".