21204245351 has 8 divisors (see below), whose sum is σ = 21836601600. Its totient is φ = 20580987960.

The previous prime is 21204245339. The next prime is 21204245369. The reversal of 21204245351 is 15354240212.

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 21204245351 - 2¹⁴ = 21204228967 is a prime.

It is a super-2 number, since 2×21204245351² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21204244351) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2269985 + ... + 2279306.

It is an arithmetic number, because the mean of its divisors is an integer number (2729575200).

Almost surely, 2^21204245351 is an apocalyptic number.

21204245351 is a deficient number, since it is larger than the sum of its proper divisors (632356249).

21204245351 is an equidigital number, since it uses as much as digits as its factorization.

21204245351 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4549429.

The product of its (nonzero) digits is 9600, while the sum is 29.

Adding to 21204245351 its reverse (15354240212), we get a palindrome (36558485563).

The spelling of 21204245351 in words is "twenty-one billion, two hundred four million, two hundred forty-five thousand, three hundred fifty-one".