21661031332113 has 8 divisors (see below), whose sum is σ = 28985640002688. Its totient is φ = 14388555108144.

The previous prime is 21661031332091. The next prime is 21661031332123. The reversal of 21661031332113 is 31123313016612.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 21661031332113 - 2⁵ = 21661031332081 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21661031332123) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 13033110681 + ... + 13033112342.

It is an arithmetic number, because the mean of its divisors is an integer number (3623205000336).

Almost surely, 2^{21661031332113} is an apocalyptic number.

It is an amenable number.

21661031332113 is a deficient number, since it is larger than the sum of its proper divisors (7324608670575).

21661031332113 is a wasteful number, since it uses less digits than its factorization.

21661031332113 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 26066223303.

The product of its (nonzero) digits is 11664, while the sum is 33.

Adding to 21661031332113 its reverse (31123313016612), we get a palindrome (52784344348725).

The spelling of 21661031332113 in words is "twenty-one trillion, six hundred sixty-one billion, thirty-one million, three hundred thirty-two thousand, one hundred thirteen".