21221523043064 has 8 divisors (see below), whose sum is σ = 39790355705760. Its totient is φ = 10610761521528.

The previous prime is 21221523043027. The next prime is 21221523043067. The reversal of 21221523043064 is 46034032512212.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (8).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21221523043067) by changing a digit.

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 as a sum of consecutive naturals, namely, 1326345190184 + ... + 1326345190199.

It is an arithmetic number, because the mean of its divisors is an integer number (4973794463220).

Almost surely, 2^{21221523043064} is an apocalyptic number.

It is an amenable number.

21221523043064 is a deficient number, since it is larger than the sum of its proper divisors (18568832662696).

21221523043064 is a wasteful number, since it uses less digits than its factorization.

21221523043064 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2652690380389 (or 2652690380385 counting only the distinct ones).

The product of its (nonzero) digits is 69120, while the sum is 35.

Adding to 21221523043064 its reverse (46034032512212), we get a palindrome (67255555555276).

The spelling of 21221523043064 in words is "twenty-one trillion, two hundred twenty-one billion, five hundred twenty-three million, forty-three thousand, sixty-four".