21451968395 has 48 divisors (see below), whose sum is σ = 30522797760. Its totient is φ = 14377271040.

The previous prime is 21451968367. The next prime is 21451968451. The reversal of 21451968395 is 59386915412.

It is not a de Polignac number, because 21451968395 - 2⁶ = 21451968331 is a prime.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 5574362 + ... + 5578208.

It is an arithmetic number, because the mean of its divisors is an integer number (635891620).

Almost surely, 2^21451968395 is an apocalyptic number.

21451968395 is a deficient number, since it is larger than the sum of its proper divisors (9070829365).

21451968395 is a wasteful number, since it uses less digits than its factorization.

21451968395 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4596 (or 4585 counting only the distinct ones).

The product of its digits is 2332800, while the sum is 53.

The spelling of 21451968395 in words is "twenty-one billion, four hundred fifty-one million, nine hundred sixty-eight thousand, three hundred ninety-five".