21213600661045 has 32 divisors (see below), whose sum is σ = 27589106369664. Its totient is φ = 15565949280000.

The previous prime is 21213600660997. The next prime is 21213600661061. The reversal of 21213600661045 is 54016600631212.

It is not a de Polignac number, because 21213600661045 - 2²⁹ = 21213063790133 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21213600660995 and 21213600661013.

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 31 ways as a sum of consecutive naturals, for example, 5324374 + ... + 8412856.

It is an arithmetic number, because the mean of its divisors is an integer number (862159574052).

Almost surely, 2^{21213600661045} is an apocalyptic number.

It is an amenable number.

21213600661045 is a deficient number, since it is larger than the sum of its proper divisors (6375505708619).

21213600661045 is a wasteful number, since it uses less digits than its factorization.

21213600661045 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3089173.

The product of its (nonzero) digits is 51840, while the sum is 37.

The spelling of 21213600661045 in words is "twenty-one trillion, two hundred thirteen billion, six hundred million, six hundred sixty-one thousand, forty-five".