21405274341776 has 40 divisors (see below), whose sum is σ = 44665839396024. Its totient is φ = 9878713436160.

The previous prime is 21405274341757. The next prime is 21405274341827. The reversal of 21405274341776 is 67714347250412.

It can be written as a sum of positive squares in 4 ways, for example, as 9695600978176 + 11709673363600 = 3113776^2 + 3421940^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 147815 + ... + 6544646.

Almost surely, 2^{21405274341776} is an apocalyptic number.

21405274341776 is a gapful number since it is divisible by the number (26) formed by its first and last digit.

It is an amenable number.

21405274341776 is an abundant number, since it is smaller than the sum of its proper divisors (23260565054248).

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

21405274341776 is a wasteful number, since it uses less digits than its factorization.

21405274341776 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6707859 (or 6707853 counting only the distinct ones).

The product of its (nonzero) digits is 7902720, while the sum is 53.

The spelling of 21405274341776 in words is "twenty-one trillion, four hundred five billion, two hundred seventy-four million, three hundred forty-one thousand, seven hundred seventy-six".