21523665626 has 16 divisors (see below), whose sum is σ = 34188816960. Its totient is φ = 10127547840.

The previous prime is 21523665619. The next prime is 21523665637. The reversal of 21523665626 is 62656632512.

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, 282881 + ... + 350811.

It is an arithmetic number, because the mean of its divisors is an integer number (2136801060).

Almost surely, 2^21523665626 is an apocalyptic number.

21523665626 is a deficient number, since it is larger than the sum of its proper divisors (12665151334).

21523665626 is a wasteful number, since it uses less digits than its factorization.

21523665626 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 77269.

The product of its digits is 777600, while the sum is 44.

The spelling of 21523665626 in words is "twenty-one billion, five hundred twenty-three million, six hundred sixty-five thousand, six hundred twenty-six".