21213155313 has 96 divisors (see below), whose sum is σ = 37066014720. Its totient is φ = 11954628000.

The previous prime is 21213155281. The next prime is 21213155317. The reversal of 21213155313 is 31355131212.

21213155313 is a `hidden beast` number, since 2 + 121 + 3 + 1 + 5 + 531 + 3 = 666.

It is not a de Polignac number, because 21213155313 - 2⁵ = 21213155281 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is not an unprimeable number, because it can be changed into a prime (21213155317) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 42173020 + ... + 42173522.

It is an arithmetic number, because the mean of its divisors is an integer number (386104320).

Almost surely, 2^21213155313 is an apocalyptic number.

It is an amenable number.

21213155313 is a deficient number, since it is larger than the sum of its proper divisors (15852859407).

21213155313 is a wasteful number, since it uses less digits than its factorization.

21213155313 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 904 (or 891 counting only the distinct ones).

The product of its digits is 2700, while the sum is 27.

Adding to 21213155313 its reverse (31355131212), we get a palindrome (52568286525).

The spelling of 21213155313 in words is "twenty-one billion, two hundred thirteen million, one hundred fifty-five thousand, three hundred thirteen".