21555560122 has 8 divisors (see below), whose sum is σ = 33207214356. Its totient is φ = 10486488672.

The previous prime is 21555560107. The next prime is 21555560123. The reversal of 21555560122 is 22106555512.

It can be written as a sum of positive squares in 2 ways, for example, as 21138542881 + 417017241 = 145391^2 + 20421^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is not an unprimeable number, because it can be changed into a prime (21555560123) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 145645603 + ... + 145645750.

Almost surely, 2^21555560122 is an apocalyptic number.

21555560122 is a deficient number, since it is larger than the sum of its proper divisors (11651654234).

21555560122 is a wasteful number, since it uses less digits than its factorization.

21555560122 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 291291392.

The product of its (nonzero) digits is 30000, while the sum is 34.

The spelling of 21555560122 in words is "twenty-one billion, five hundred fifty-five million, five hundred sixty thousand, one hundred twenty-two".