21213611540663 has 2 divisors, whose sum is σ = 21213611540664. Its totient is φ = 21213611540662.

The previous prime is 21213611540651. The next prime is 21213611540707. The reversal of 21213611540663 is 36604511631212.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21213611540663 - 2⁶ = 21213611540599 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 21213611540663.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21213611540633) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10606805770331 + 10606805770332.

It is an arithmetic number, because the mean of its divisors is an integer number (10606805770332).

Almost surely, 2^{21213611540663} is an apocalyptic number.

21213611540663 is a deficient number, since it is larger than the sum of its proper divisors (1).

21213611540663 is an equidigital number, since it uses as much as digits as its factorization.

21213611540663 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 155520, while the sum is 41.

The spelling of 21213611540663 in words is "twenty-one trillion, two hundred thirteen billion, six hundred eleven million, five hundred forty thousand, six hundred sixty-three".