21018210093 has 6 divisors (see below), whose sum is σ = 30359636814. Its totient is φ = 14012140056.

The previous prime is 21018210041. The next prime is 21018210097. The reversal of 21018210093 is 39001281012.

It can be written as a sum of positive squares in only one way, i.e., 11967922404 + 9050287689 = 109398^2 + 95133^2 .

It is not a de Polignac number, because 21018210093 - 2²⁴ = 21001432877 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21018210097) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 1167678330 + ... + 1167678347.

It is an arithmetic number, because the mean of its divisors is an integer number (5059939469).

Almost surely, 2^21018210093 is an apocalyptic number.

It is an amenable number.

21018210093 is a deficient number, since it is larger than the sum of its proper divisors (9341426721).

21018210093 is a wasteful number, since it uses less digits than its factorization.

21018210093 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2335356683 (or 2335356680 counting only the distinct ones).

The product of its (nonzero) digits is 864, while the sum is 27.

The spelling of 21018210093 in words is "twenty-one billion, eighteen million, two hundred ten thousand, ninety-three".