21455944061216 has 48 divisors (see below), whose sum is σ = 48297611355840. Its totient is φ = 9191264175360.

The previous prime is 21455944061203. The next prime is 21455944061267. The reversal of 21455944061216 is 61216044955412.

It is a happy number.

It is a hoax number, since the sum of its digits (50) coincides with the sum of the digits of its distinct prime factors.

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 7 ways as a sum of consecutive naturals, for example, 21066086 + ... + 22061093.

It is an arithmetic number, because the mean of its divisors is an integer number (1006200236580).

Almost surely, 2^{21455944061216} is an apocalyptic number.

It is an amenable number.

21455944061216 is an abundant number, since it is smaller than the sum of its proper divisors (26841667294624).

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

21455944061216 is a wasteful number, since it uses less digits than its factorization.

21455944061216 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 43129417 (or 43129409 counting only the distinct ones).

The product of its (nonzero) digits is 2073600, while the sum is 50.

The spelling of 21455944061216 in words is "twenty-one trillion, four hundred fifty-five billion, nine hundred forty-four million, sixty-one thousand, two hundred sixteen".