21456066240 has 224 divisors, whose sum is σ = 86505653760. Its totient is φ = 4904229888.

The previous prime is 21456066157. The next prime is 21456066241. The reversal of 21456066240 is 4266065412.

21456066240 is a `hidden beast` number, since 2 + 1 + 4 + 5 + 606 + 6 + 2 + 40 = 666.

It is a tau number, because it is divible by the number of its divisors (224).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a junction number, because it is equal to n+sod(n) for n = 21456066195 and 21456066204.

It is not an unprimeable number, because it can be changed into a prime (21456066241) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 116902 + ... + 237861.

Almost surely, 2^21456066240 is an apocalyptic number.

21456066240 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21456066240 is an abundant number, since it is smaller than the sum of its proper divisors (65049587520).

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

21456066240 is a wasteful number, since it uses less digits than its factorization.

21456066240 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 354796 (or 354780 counting only the distinct ones).

The product of its (nonzero) digits is 69120, while the sum is 36.

The spelling of 21456066240 in words is "twenty-one billion, four hundred fifty-six million, sixty-six thousand, two hundred forty".