21568872066990 has 32 divisors (see below), whose sum is σ = 51777196077600. Its totient is φ = 5750376649344.

The previous prime is 21568872066913. The next prime is 21568872067073. The reversal of 21568872066990 is 9966027886512.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 82527889 + ... + 82788828.

It is an arithmetic number, because the mean of its divisors is an integer number (1618037377425).

Almost surely, 2^{21568872066990} is an apocalyptic number.

21568872066990 is an abundant number, since it is smaller than the sum of its proper divisors (30208324010610).

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

21568872066990 is a wasteful number, since it uses less digits than its factorization.

21568872066990 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 165321076.

The product of its (nonzero) digits is 156764160, while the sum is 69.

The spelling of 21568872066990 in words is "twenty-one trillion, five hundred sixty-eight billion, eight hundred seventy-two million, sixty-six thousand, nine hundred ninety".