21201663360 has 128 divisors (see below), whose sum is σ = 69910840800. Its totient is φ = 5458804736.

The previous prime is 21201663347. The next prime is 21201663383. The reversal of 21201663360 is 6336610212.

It is a tau number, because it is divible by the number of its divisors (128).

It is a Harshad number since it is a multiple of its sum of digits (30).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 134709 + ... + 246068.

Almost surely, 2^21201663360 is an apocalyptic number.

21201663360 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21201663360 is an abundant number, since it is smaller than the sum of its proper divisors (48709177440).

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

21201663360 is a wasteful number, since it uses less digits than its factorization.

21201663360 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 380828 (or 380816 counting only the distinct ones).

The product of its (nonzero) digits is 7776, while the sum is 30.

The spelling of 21201663360 in words is "twenty-one billion, two hundred one million, six hundred sixty-three thousand, three hundred sixty".