21603331164351 has 16 divisors (see below), whose sum is σ = 28811175694560. Its totient is φ = 14398854053760.

The previous prime is 21603331164271. The next prime is 21603331164409. The reversal of 21603331164351 is 15346113330612.

It is not a de Polignac number, because 21603331164351 - 2⁷ = 21603331164223 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21603331162351) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 349645081 + ... + 349706861.

It is an arithmetic number, because the mean of its divisors is an integer number (1800698480910).

Almost surely, 2^{21603331164351} is an apocalyptic number.

21603331164351 is a deficient number, since it is larger than the sum of its proper divisors (7207844530209).

21603331164351 is a wasteful number, since it uses less digits than its factorization.

21603331164351 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 87146.

The product of its (nonzero) digits is 116640, while the sum is 39.

Adding to 21603331164351 its reverse (15346113330612), we get a palindrome (36949444494963).

The spelling of 21603331164351 in words is "twenty-one trillion, six hundred three billion, three hundred thirty-one million, one hundred sixty-four thousand, three hundred fifty-one".