21661030363120 has 40 divisors (see below), whose sum is σ = 50525940914064. Its totient is φ = 8636189294592.

The previous prime is 21661030363111. The next prime is 21661030363153. The reversal of 21661030363120 is 2136303016612.

It is a tau number, because it is divible by the number of its divisors (40).

It is a super-2 number, since 2×21661030363120² (a number of 27 digits) contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 440957329 + ... + 441006448.

Almost surely, 2^{21661030363120} is an apocalyptic number.

21661030363120 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21661030363120 is an abundant number, since it is smaller than the sum of its proper divisors (28864910550944).

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

21661030363120 is a wasteful number, since it uses less digits than its factorization.

21661030363120 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 881964097 (or 881964091 counting only the distinct ones).

The product of its (nonzero) digits is 23328, while the sum is 34.

Adding to 21661030363120 its reverse (2136303016612), we get a palindrome (23797333379732).

The spelling of 21661030363120 in words is "twenty-one trillion, six hundred sixty-one billion, thirty million, three hundred sixty-three thousand, one hundred twenty".