21356206163061 has 64 divisors (see below), whose sum is σ = 35995927535616. Its totient is φ = 10939609612800.

The previous prime is 21356206163059. The next prime is 21356206163087. The reversal of 21356206163061 is 16036160265312.

It is not a de Polignac number, because 21356206163061 - 2¹ = 21356206163059 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21356206163051) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 73326756 + ... + 73617426.

It is an arithmetic number, because the mean of its divisors is an integer number (562436367744).

Almost surely, 2^{21356206163061} is an apocalyptic number.

21356206163061 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

It is an amenable number.

21356206163061 is a deficient number, since it is larger than the sum of its proper divisors (14639721372555).

21356206163061 is a wasteful number, since it uses less digits than its factorization.

21356206163061 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 295122.

The product of its (nonzero) digits is 233280, while the sum is 42.

The spelling of 21356206163061 in words is "twenty-one trillion, three hundred fifty-six billion, two hundred six million, one hundred sixty-three thousand, sixty-one".