21348165204 has 18 divisors (see below), whose sum is σ = 53963417690. Its totient is φ = 7116055056.

The previous prime is 21348165199. The next prime is 21348165211. The reversal of 21348165204 is 40256184312.

It is a happy number.

21348165204 is a `hidden beast` number, since 21 + 34 + 81 + 6 + 520 + 4 = 666.

It can be written as a sum of positive squares in only one way, i.e., 21074328900 + 273836304 = 145170^2 + 16548^2 .

It is a tau number, because it is divible by the number of its divisors (18).

It is a Harshad number since it is a multiple of its sum of digits (36), and also a Moran number because the ratio is a prime number: 593004589 = 21348165204 / (2 + 1 + 3 + 4 + 8 + 1 + 6 + 5 + 2 + 0 + 4).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 296502259 + ... + 296502330.

Almost surely, 2^21348165204 is an apocalyptic number.

It is an amenable number.

21348165204 is an abundant number, since it is smaller than the sum of its proper divisors (32615252486).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21348165204 is a wasteful number, since it uses less digits than its factorization.

21348165204 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 593004599 (or 593004594 counting only the distinct ones).

The product of its (nonzero) digits is 46080, while the sum is 36.

The spelling of 21348165204 in words is "twenty-one billion, three hundred forty-eight million, one hundred sixty-five thousand, two hundred four".