21517706152240 has 80 divisors (see below), whose sum is σ = 52998939823968. Its totient is φ = 8096591720448.

The previous prime is 21517706152231. The next prime is 21517706152247. The reversal of 21517706152240 is 4225160771512.

It is a tau number, because it is divible by the number of its divisors (80).

It is not an unprimeable number, because it can be changed into a prime (21517706152247) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1463682 + ... + 6721441.

Almost surely, 2^{21517706152240} is an apocalyptic number.

21517706152240 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21517706152240 is an abundant number, since it is smaller than the sum of its proper divisors (31481233671728).

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

21517706152240 is a wasteful number, since it uses less digits than its factorization.

21517706152240 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8187086 (or 8187080 counting only the distinct ones).

The product of its (nonzero) digits is 235200, while the sum is 43.

The spelling of 21517706152240 in words is "twenty-one trillion, five hundred seventeen billion, seven hundred six million, one hundred fifty-two thousand, two hundred forty".