21354664722772 has 6 divisors (see below), whose sum is σ = 37370663264858. Its totient is φ = 10677332361384.

The previous prime is 21354664722761. The next prime is 21354664722793. The reversal of 21354664722772 is 27722746645312.

It is a happy number.

It can be written as a sum of positive squares in only one way, i.e., 16926855579076 + 4427809143696 = 4114226^2 + 2104236^2 .

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2669333090343 + ... + 2669333090350.

Almost surely, 2^{21354664722772} is an apocalyptic number.

It is an amenable number.

21354664722772 is a deficient number, since it is larger than the sum of its proper divisors (16015998542086).

21354664722772 is a wasteful number, since it uses less digits than its factorization.

21354664722772 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5338666180697 (or 5338666180695 counting only the distinct ones).

The product of its digits is 47416320, while the sum is 58.

The spelling of 21354664722772 in words is "twenty-one trillion, three hundred fifty-four billion, six hundred sixty-four million, seven hundred twenty-two thousand, seven hundred seventy-two".