21213313400400 has 120 divisors (see below), whose sum is σ = 74130887965344. Its totient is φ = 5142621427200.

The previous prime is 21213313400371. The next prime is 21213313400417. The reversal of 21213313400400 is 400431331212.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (120).

It is a Harshad number since it is a multiple of its sum of digits (24).

It is a congruent number.

It is an unprimeable number.

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 23 ways as a sum of consecutive naturals, for example, 803521399 + ... + 803547798.

Almost surely, 2^{21213313400400} is an apocalyptic number.

21213313400400 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21213313400400 is an abundant number, since it is smaller than the sum of its proper divisors (52917574564944).

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

21213313400400 is a wasteful number, since it uses less digits than its factorization.

21213313400400 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1607069229 (or 1607069218 counting only the distinct ones).

The product of its (nonzero) digits is 1728, while the sum is 24.

Adding to 21213313400400 its reverse (400431331212), we get a palindrome (21613744731612).

The spelling of 21213313400400 in words is "twenty-one trillion, two hundred thirteen billion, three hundred thirteen million, four hundred thousand, four hundred".