21214036536660 has 144 divisors (see below), whose sum is σ = 70242869354112. Its totient is φ = 5139595718400.

The previous prime is 21214036536617. The next prime is 21214036536677. The reversal of 21214036536660 is 6663563041212.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 151731 + ... + 6515450.

It is an arithmetic number, because the mean of its divisors is an integer number (487797703848).

Almost surely, 2^{21214036536660} is an apocalyptic number.

21214036536660 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21214036536660, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (35121434677056).

21214036536660 is an abundant number, since it is smaller than the sum of its proper divisors (49028832817452).

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

21214036536660 is a wasteful number, since it uses less digits than its factorization.

21214036536660 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6668814 (or 6668809 counting only the distinct ones).

The product of its (nonzero) digits is 933120, while the sum is 45.

Adding to 21214036536660 its reverse (6663563041212), we get a palindrome (27877599577872).

The spelling of 21214036536660 in words is "twenty-one trillion, two hundred fourteen billion, thirty-six million, five hundred thirty-six thousand, six hundred sixty".