21115666506010 has 16 divisors (see below), whose sum is σ = 38384518521672. Its totient is φ = 8362640200000.

The previous prime is 21115666506007. The next prime is 21115666506013. The reversal of 21115666506010 is 1060566651112.

It is an interprime number because it is at equal distance from previous prime (21115666506007) and next prime (21115666506013).

It can be written as a sum of positive squares in 4 ways, for example, as 20093066235841 + 1022600270169 = 4482529^2 + 1011237^2 .

It is a super-2 number, since 2×21115666506010² (a number of 27 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (21115666506013) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 10453299241 + ... + 10453301260.

Almost surely, 2^{21115666506010} is an apocalyptic number.

21115666506010 is a deficient number, since it is larger than the sum of its proper divisors (17268852015662).

21115666506010 is a wasteful number, since it uses less digits than its factorization.

21115666506010 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20906600609.

The product of its (nonzero) digits is 64800, while the sum is 40.

The spelling of 21115666506010 in words is "twenty-one trillion, one hundred fifteen billion, six hundred sixty-six million, five hundred six thousand, ten".