21352560555690 has 384 divisors, whose sum is σ = 71498587410432. Its totient is φ = 4300100628480.

The previous prime is 21352560555619. The next prime is 21352560555709. The reversal of 21352560555690 is 9655506525312.

21352560555690 is a `hidden beast` number, since 2 + 1 + 3 + 5 + 25 + 6 + 0 + 55 + 569 + 0 = 666.

It is a super-2 number, since 2×21352560555690² (a number of 27 digits) contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 191 ways as a sum of consecutive naturals, for example, 17957932 + ... + 19110008.

It is an arithmetic number, because the mean of its divisors is an integer number (186194238048).

Almost surely, 2^{21352560555690} is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21352560555690, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (35749293705216).

21352560555690 is an abundant number, since it is smaller than the sum of its proper divisors (50146026854742).

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

21352560555690 is a wasteful number, since it uses less digits than its factorization.

21352560555690 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1152214 (or 1152211 counting only the distinct ones).

The product of its (nonzero) digits is 12150000, while the sum is 54.

The spelling of 21352560555690 in words is "twenty-one trillion, three hundred fifty-two billion, five hundred sixty million, five hundred fifty-five thousand, six hundred ninety".