21566127802 has 16 divisors (see below), whose sum is σ = 35150227200. Its totient is φ = 9886000320.

The previous prime is 21566127787. The next prime is 21566127839. The reversal of 21566127802 is 20872166512.

It is an unprimeable number.

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 7 ways as a sum of consecutive naturals, for example, 9152527 + ... + 9154882.

It is an arithmetic number, because the mean of its divisors is an integer number (2196889200).

Almost surely, 2^21566127802 is an apocalyptic number.

21566127802 is a deficient number, since it is larger than the sum of its proper divisors (13584099398).

21566127802 is a wasteful number, since it uses less digits than its factorization.

21566127802 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 18307461.

The product of its (nonzero) digits is 80640, while the sum is 40.

The spelling of 21566127802 in words is "twenty-one billion, five hundred sixty-six million, one hundred twenty-seven thousand, eight hundred two".