21424670172768 has 96 divisors (see below), whose sum is σ = 58686559658496. Its totient is φ = 6830868768768.

The previous prime is 21424670172767. The next prime is 21424670172809. The reversal of 21424670172768 is 86727107642412.

It is a happy number.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21424670172767) 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, 97623096 + ... + 97842312.

It is an arithmetic number, because the mean of its divisors is an integer number (611318329776).

Almost surely, 2^{21424670172768} is an apocalyptic number.

It is an amenable number.

21424670172768 is an abundant number, since it is smaller than the sum of its proper divisors (37261889485728).

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

21424670172768 is a wasteful number, since it uses less digits than its factorization.

21424670172768 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 263516 (or 263508 counting only the distinct ones).

The product of its (nonzero) digits is 12644352, while the sum is 57.

The spelling of 21424670172768 in words is "twenty-one trillion, four hundred twenty-four billion, six hundred seventy million, one hundred seventy-two thousand, seven hundred sixty-eight".