21219274368 has 96 divisors (see below), whose sum is σ = 61130721600. Its totient is φ = 7064977920.

The previous prime is 21219274367. The next prime is 21219274399. The reversal of 21219274368 is 86347291212.

21219274368 is a `hidden beast` number, since 2 + 1 + 2 + 19 + 274 + 368 = 666.

It is a tau number, because it is divible by the number of its divisors (96).

It is a Smith number, since the sum of its digits (45) coincides with the sum of the digits of its prime factors.

It is not an unprimeable number, because it can be changed into a prime (21219274367) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1039363 + ... + 1059581.

It is an arithmetic number, because the mean of its divisors is an integer number (636778350).

Almost surely, 2^21219274368 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21219274368, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (30565360800).

21219274368 is an abundant number, since it is smaller than the sum of its proper divisors (39911447232).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21219274368 is a wasteful number, since it uses less digits than its factorization.

21219274368 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 21150 (or 21135 counting only the distinct ones).

The product of its digits is 290304, while the sum is 45.

The spelling of 21219274368 in words is "twenty-one billion, two hundred nineteen million, two hundred seventy-four thousand, three hundred sixty-eight".