21799653120 has 720 divisors, whose sum is σ = 91114161600. Its totient is φ = 4974649344.

The previous prime is 21799653079. The next prime is 21799653131. The reversal of 21799653120 is 2135699712.

It is a happy number.

21799653120 is a `hidden beast` number, since 2 + 1 + 7 + 9 + 96 + 531 + 20 = 666.

It is a tau number, because it is divible by the number of its divisors (720).

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 79 ways as a sum of consecutive naturals, for example, 35561934 + ... + 35562546.

Almost surely, 2^21799653120 is an apocalyptic number.

21799653120 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21799653120, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (45557080800).

21799653120 is an abundant number, since it is smaller than the sum of its proper divisors (69314508480).

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

21799653120 is an frugal number, since it uses more digits than its factorization.

21799653120 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 667 (or 630 counting only the distinct ones).

The product of its (nonzero) digits is 204120, while the sum is 45.

The spelling of 21799653120 in words is "twenty-one billion, seven hundred ninety-nine million, six hundred fifty-three thousand, one hundred twenty".