21354661335616 has 56 divisors (see below), whose sum is σ = 48490858665536. Its totient is φ = 9140368596480.

The previous prime is 21354661335611. The next prime is 21354661335617. The reversal of 21354661335616 is 61653316645312.

It is a tau number, because it is divible by the number of its divisors (56).

It is not an unprimeable number, because it can be changed into a prime (21354661335611) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 29931195 + ... + 30636346.

It is an arithmetic number, because the mean of its divisors is an integer number (865908190456).

Almost surely, 2^{21354661335616} is an apocalyptic number.

It is an amenable number.

21354661335616 is an abundant number, since it is smaller than the sum of its proper divisors (27136197329920).

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

21354661335616 is an equidigital number, since it uses as much as digits as its factorization.

21354661335616 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 60568347 (or 60568337 counting only the distinct ones).

The product of its digits is 6998400, while the sum is 52.

The spelling of 21354661335616 in words is "twenty-one trillion, three hundred fifty-four billion, six hundred sixty-one million, three hundred thirty-five thousand, six hundred sixteen".