21401347472 has 10 divisors (see below), whose sum is σ = 41465110758. Its totient is φ = 10700673728.

The previous prime is 21401347463. The next prime is 21401347483. The reversal of 21401347472 is 27474310412.

It can be written as a sum of positive squares in only one way, i.e., 21186549136 + 214798336 = 145556^2 + 14656^2 .

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 as a sum of consecutive naturals, namely, 668792093 + ... + 668792124.

Almost surely, 2^21401347472 is an apocalyptic number.

It is an amenable number.

21401347472 is a deficient number, since it is larger than the sum of its proper divisors (20063763286).

21401347472 is a wasteful number, since it uses less digits than its factorization.

21401347472 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1337584225 (or 1337584219 counting only the distinct ones).

The product of its (nonzero) digits is 37632, while the sum is 35.

Adding to 21401347472 its reverse (27474310412), we get a palindrome (48875657884).

The spelling of 21401347472 in words is "twenty-one billion, four hundred one million, three hundred forty-seven thousand, four hundred seventy-two".