21013000123208 has 16 divisors (see below), whose sum is σ = 39488312879280. Its totient is φ = 10482783355408.

The previous prime is 21013000123201. The next prime is 21013000123259. The reversal of 21013000123208 is 80232100031012.

It is a happy number.

It is a super-2 number, since 2×21013000123208² (a number of 27 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (21013000123201) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2964584510 + ... + 2964591597.

It is an arithmetic number, because the mean of its divisors is an integer number (2468019554955).

Almost surely, 2^{21013000123208} is an apocalyptic number.

It is an amenable number.

21013000123208 is a deficient number, since it is larger than the sum of its proper divisors (18475312756072).

21013000123208 is a wasteful number, since it uses less digits than its factorization.

21013000123208 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5929176556 (or 5929176552 counting only the distinct ones).

The product of its (nonzero) digits is 576, while the sum is 23.

The spelling of 21013000123208 in words is "twenty-one trillion, thirteen billion, one hundred twenty-three thousand, two hundred eight".