21213556362611 has 16 divisors (see below), whose sum is σ = 21687152433408. Its totient is φ = 20745255276000.

The previous prime is 21213556362553. The next prime is 21213556362613. The reversal of 21213556362611 is 11626365531212.

It is a happy number.

It is a cyclic number.

It is not a de Polignac number, because 21213556362611 - 2²² = 21213552168307 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21213556362613) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 33274916 + ... + 33906446.

It is an arithmetic number, because the mean of its divisors is an integer number (1355447027088).

Almost surely, 2^{21213556362611} is an apocalyptic number.

21213556362611 is a deficient number, since it is larger than the sum of its proper divisors (473596070797).

21213556362611 is a wasteful number, since it uses less digits than its factorization.

21213556362611 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 635722.

The product of its digits is 388800, while the sum is 44.

The spelling of 21213556362611 in words is "twenty-one trillion, two hundred thirteen billion, five hundred fifty-six million, three hundred sixty-two thousand, six hundred eleven".