21214036536655 has 16 divisors (see below), whose sum is σ = 25486374057984. Its totient is φ = 16951550568480.

The previous prime is 21214036536617. The next prime is 21214036536677. The reversal of 21214036536655 is 55663563041212.

It is not a de Polignac number, because 21214036536655 - 2⁴³ = 12417943514447 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21214036536599 and 21214036536608.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 20420250 + ... + 21433960.

It is an arithmetic number, because the mean of its divisors is an integer number (1592898378624).

Almost surely, 2^{21214036536655} is an apocalyptic number.

21214036536655 is a deficient number, since it is larger than the sum of its proper divisors (4272337521329).

21214036536655 is a wasteful number, since it uses less digits than its factorization.

21214036536655 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1018566.

The product of its (nonzero) digits is 3888000, while the sum is 49.

Adding to 21214036536655 its reverse (55663563041212), we get a palindrome (76877599577867).

The spelling of 21214036536655 in words is "twenty-one trillion, two hundred fourteen billion, thirty-six million, five hundred thirty-six thousand, six hundred fifty-five".