21164402045 has 8 divisors (see below), whose sum is σ = 25597261824. Its totient is φ = 16798202064.

The previous prime is 21164402041. The next prime is 21164402047. The reversal of 21164402045 is 54020446112.

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

It is a cyclic number.

It is not a de Polignac number, because 21164402045 - 2² = 21164402041 is a prime.

It is a super-3 number, since 3×21164402045³ (a number of 32 digits) contains 333 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21164401999 and 21164402017.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21164402041) 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, 16664249 + ... + 16665518.

It is an arithmetic number, because the mean of its divisors is an integer number (3199657728).

Almost surely, 2^21164402045 is an apocalyptic number.

It is an amenable number.

21164402045 is a deficient number, since it is larger than the sum of its proper divisors (4432859779).

21164402045 is a wasteful number, since it uses less digits than its factorization.

21164402045 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 33329899.

The product of its (nonzero) digits is 7680, while the sum is 29.

Adding to 21164402045 its reverse (54020446112), we get a palindrome (75184848157).

The spelling of 21164402045 in words is "twenty-one billion, one hundred sixty-four million, four hundred two thousand, forty-five".