21155211311416 has 128 divisors (see below), whose sum is σ = 51104334274560. Its totient is φ = 7985051020800.

The previous prime is 21155211311407. The next prime is 21155211311441. The reversal of 21155211311416 is 61411311255112.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 4999071 + ... + 8203726.

It is an arithmetic number, because the mean of its divisors is an integer number (399252611520).

Almost surely, 2^{21155211311416} is an apocalyptic number.

21155211311416 is a gapful number since it is divisible by the number (26) formed by its first and last digit.

It is an amenable number.

21155211311416 is an abundant number, since it is smaller than the sum of its proper divisors (29949122963144).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21155211311416 is a wasteful number, since it uses less digits than its factorization.

21155211311416 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13202925 (or 13202921 counting only the distinct ones).

The product of its digits is 7200, while the sum is 34.

Adding to 21155211311416 its reverse (61411311255112), we get a palindrome (82566522566528).

The spelling of 21155211311416 in words is "twenty-one trillion, one hundred fifty-five billion, two hundred eleven million, three hundred eleven thousand, four hundred sixteen".