21235716772 has 12 divisors (see below), whose sum is σ = 37164763440. Its totient is φ = 10617212936.

The previous prime is 21235716737. The next prime is 21235716793. The reversal of 21235716772 is 27761753212.

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 3 ways as a sum of consecutive naturals, for example, 83122 + ... + 222217.

It is an arithmetic number, because the mean of its divisors is an integer number (3097063620).

Almost surely, 2^21235716772 is an apocalyptic number.

It is an amenable number.

21235716772 is a deficient number, since it is larger than the sum of its proper divisors (15929046668).

21235716772 is a wasteful number, since it uses less digits than its factorization.

21235716772 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 322730 (or 322728 counting only the distinct ones).

The product of its digits is 246960, while the sum is 43.

The spelling of 21235716772 in words is "twenty-one billion, two hundred thirty-five million, seven hundred sixteen thousand, seven hundred seventy-two".