21304134555 has 64 divisors (see below), whose sum is σ = 37468873728. Its totient is φ = 10250831360.

The previous prime is 21304134539. The next prime is 21304134569. The reversal of 21304134555 is 55543140312.

It is not a de Polignac number, because 21304134555 - 2⁴ = 21304134539 is a prime.

It is a super-2 number, since 2×21304134555² (a number of 21 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (33).

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 21030229 + ... + 21031241.

It is an arithmetic number, because the mean of its divisors is an integer number (585451152).

Almost surely, 2^21304134555 is an apocalyptic number.

21304134555 is a deficient number, since it is larger than the sum of its proper divisors (16164739173).

21304134555 is a wasteful number, since it uses less digits than its factorization.

21304134555 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1876.

The product of its (nonzero) digits is 36000, while the sum is 33.

Adding to 21304134555 its reverse (55543140312), we get a palindrome (76847274867).

The spelling of 21304134555 in words is "twenty-one billion, three hundred four million, one hundred thirty-four thousand, five hundred fifty-five".