21742743619680 has 96 divisors (see below), whose sum is σ = 68683664587104. Its totient is φ = 5781639806976.

The previous prime is 21742743619643. The next prime is 21742743619697. The reversal of 21742743619680 is 8691634724712.

It is a tau number, because it is divible by the number of its divisors (96).

It is a super-2 number, since 2×21742743619680² (a number of 27 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (60).

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, 63991159 + ... + 64330038.

It is an arithmetic number, because the mean of its divisors is an integer number (715454839449).

Almost surely, 2^{21742743619680} is an apocalyptic number.

21742743619680 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21742743619680 is an abundant number, since it is smaller than the sum of its proper divisors (46940920967424).

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

21742743619680 is a wasteful number, since it uses less digits than its factorization.

21742743619680 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 128321568 (or 128321560 counting only the distinct ones).

The product of its (nonzero) digits is 24385536, while the sum is 60.

The spelling of 21742743619680 in words is "twenty-one trillion, seven hundred forty-two billion, seven hundred forty-three million, six hundred nineteen thousand, six hundred eighty".