21993379488 has 72 divisors (see below), whose sum is σ = 62578702368. Its totient is φ = 7327020672.

The previous prime is 21993379433. The next prime is 21993379561. The reversal of 21993379488 is 88497339912.

21993379488 is a `hidden beast` number, since 219 + 9 + 3 + 379 + 48 + 8 = 666.

It is a tau number, because it is divible by the number of its divisors (72).

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 517245 + ... + 558147.

It is an arithmetic number, because the mean of its divisors is an integer number (869148644).

Almost surely, 2^21993379488 is an apocalyptic number.

It is an amenable number.

21993379488 is an abundant number, since it is smaller than the sum of its proper divisors (40585322880).

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

21993379488 is a wasteful number, since it uses less digits than its factorization.

21993379488 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 42786 (or 42775 counting only the distinct ones).

The product of its digits is 23514624, while the sum is 63.

The spelling of 21993379488 in words is "twenty-one billion, nine hundred ninety-three million, three hundred seventy-nine thousand, four hundred eighty-eight".