21466021093 has 18 divisors (see below), whose sum is σ = 23767527462. Its totient is φ = 19372026960.

The previous prime is 21466021079. The next prime is 21466021111. The reversal of 21466021093 is 39012066412.

It is a happy number.

It can be written as a sum of positive squares in only one way, i.e., 16543876129 + 4922144964 = 128623^2 + 70158^2 .

It is a de Polignac number, because none of the positive numbers 2^k-21466021093 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21466021043) by changing a digit.

It is a polite number, since it can be written in 17 ways as a sum of consecutive naturals, for example, 20193280 + ... + 20194342.

Almost surely, 2^21466021093 is an apocalyptic number.

It is an amenable number.

21466021093 is a deficient number, since it is larger than the sum of its proper divisors (2301506369).

21466021093 is an equidigital number, since it uses as much as digits as its factorization.

21466021093 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2305 (or 1231 counting only the distinct ones).

The product of its (nonzero) digits is 15552, while the sum is 34.

The spelling of 21466021093 in words is "twenty-one billion, four hundred sixty-six million, twenty-one thousand, ninety-three".