21046165512100 has 81 divisors (see below), whose sum is σ = 45927359853417. Its totient is φ = 8371323924480.

The previous prime is 21046165512041. The next prime is 21046165512109. The reversal of 21046165512100 is 121556164012.

The square root of 21046165512100 is 4587610.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in 13 ways, for example, as 19575262267236 + 1470903244864 = 4424394^2 + 1212808^2 .

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21046165512109) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 26 ways as a sum of consecutive naturals, for example, 8854086112 + ... + 8854088488.

Almost surely, 2^{21046165512100} is an apocalyptic number.

21046165512100 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

21046165512100 is the 4587610-th square number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21046165512100

21046165512100 is an abundant number, since it is smaller than the sum of its proper divisors (24881194341317).

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

21046165512100 is an frugal number, since it uses more digits than its factorization.

21046165512100 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5154 (or 2577 counting only the distinct ones).

The product of its (nonzero) digits is 14400, while the sum is 34.

The spelling of 21046165512100 in words is "twenty-one trillion, forty-six billion, one hundred sixty-five million, five hundred twelve thousand, one hundred".