21523304155 has 8 divisors (see below), whose sum is σ = 27347257152. Its totient is φ = 16205781888.

The previous prime is 21523304141. The next prime is 21523304167. The reversal of 21523304155 is 55140332512.

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 21523304155 - 2⁹ = 21523303643 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 126607587 + ... + 126607756.

It is an arithmetic number, because the mean of its divisors is an integer number (3418407144).

Almost surely, 2^21523304155 is an apocalyptic number.

21523304155 is a deficient number, since it is larger than the sum of its proper divisors (5823952997).

21523304155 is a wasteful number, since it uses less digits than its factorization.

21523304155 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 253215365.

The product of its (nonzero) digits is 18000, while the sum is 31.

Adding to 21523304155 its reverse (55140332512), we get a palindrome (76663636667).

The spelling of 21523304155 in words is "twenty-one billion, five hundred twenty-three million, three hundred four thousand, one hundred fifty-five".