21447800001 has 16 divisors (see below), whose sum is σ = 33446862400. Its totient is φ = 13545978624.

The previous prime is 21447799991. The next prime is 21447800029. The reversal of 21447800001 is 10000874412.

It is not a de Polignac number, because 21447800001 - 2⁷ = 21447799873 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21447800041) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 20903776 + ... + 20904801.

It is an arithmetic number, because the mean of its divisors is an integer number (2090428900).

Almost surely, 2^21447800001 is an apocalyptic number.

It is an amenable number.

21447800001 is a deficient number, since it is larger than the sum of its proper divisors (11999062399).

21447800001 is a wasteful number, since it uses less digits than its factorization.

21447800001 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 41808605 (or 41808599 counting only the distinct ones).

The product of its (nonzero) digits is 1792, while the sum is 27.

The spelling of 21447800001 in words is "twenty-one billion, four hundred forty-seven million, eight hundred thousand, one".