21304134551 has 8 divisors (see below), whose sum is σ = 24454842240. Its totient is φ = 18180241848.

The previous prime is 21304134539. The next prime is 21304134569. The reversal of 21304134551 is 15543140312.

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 21304134551 - 2²² = 21299940247 is a prime.

It is a super-2 number, since 2×21304134551² (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 (21304134451) 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, 6702041 + ... + 6705218.

It is an arithmetic number, because the mean of its divisors is an integer number (3056855280).

Almost surely, 2^21304134551 is an apocalyptic number.

21304134551 is a deficient number, since it is larger than the sum of its proper divisors (3150707689).

21304134551 is a wasteful number, since it uses less digits than its factorization.

21304134551 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13407493.

The product of its (nonzero) digits is 7200, while the sum is 29.

Adding to 21304134551 its reverse (15543140312), we get a palindrome (36847274863).

The spelling of 21304134551 in words is "twenty-one billion, three hundred four million, one hundred thirty-four thousand, five hundred fifty-one".