21213433351550 has 48 divisors (see below), whose sum is σ = 43051565273472. Its totient is φ = 7712617250400.

The previous prime is 21213433351427. The next prime is 21213433351567. The reversal of 21213433351550 is 5515333431212.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 267794 + ... + 6519093.

It is an arithmetic number, because the mean of its divisors is an integer number (896907609864).

Almost surely, 2^{21213433351550} is an apocalyptic number.

21213433351550 is an abundant number, since it is smaller than the sum of its proper divisors (21838131921922).

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

21213433351550 is a wasteful number, since it uses less digits than its factorization.

21213433351550 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6792593 (or 6792588 counting only the distinct ones).

The product of its (nonzero) digits is 162000, while the sum is 38.

Adding to 21213433351550 its reverse (5515333431212), we get a palindrome (26728766782762).

The spelling of 21213433351550 in words is "twenty-one trillion, two hundred thirteen billion, four hundred thirty-three million, three hundred fifty-one thousand, five hundred fifty".