21552691970 has 16 divisors (see below), whose sum is σ = 41076895608. Its totient is φ = 8113954560.

The previous prime is 21552691969. The next prime is 21552692003. The reversal of 21552691970 is 7919625512.

It can be written as a sum of positive squares in 4 ways, for example, as 21536443009 + 16248961 = 146753^2 + 4031^2 .

It is a Curzon number.

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, 63390101 + ... + 63390440.

Almost surely, 2^21552691970 is an apocalyptic number.

21552691970 is a deficient number, since it is larger than the sum of its proper divisors (19524203638).

21552691970 is a wasteful number, since it uses less digits than its factorization.

21552691970 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 126780565.

The product of its (nonzero) digits is 340200, while the sum is 47.

The spelling of 21552691970 in words is "twenty-one billion, five hundred fifty-two million, six hundred ninety-one thousand, nine hundred seventy".