21234145554 has 12 divisors (see below), whose sum is σ = 46007315406. Its totient is φ = 7078048512.

The previous prime is 21234145523. The next prime is 21234145561. The reversal of 21234145554 is 45554143212.

21234145554 is a `hidden beast` number, since 2 + 1 + 23 + 41 + 45 + 554 = 666.

It can be written as a sum of positive squares in only one way, i.e., 17762225625 + 3471919929 = 133275^2 + 58923^2 .

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, 589837359 + ... + 589837394.

Almost surely, 2^21234145554 is an apocalyptic number.

21234145554 is an abundant number, since it is smaller than the sum of its proper divisors (24773169852).

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

21234145554 is a wasteful number, since it uses less digits than its factorization.

21234145554 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1179674761 (or 1179674758 counting only the distinct ones).

The product of its digits is 96000, while the sum is 36.

Adding to 21234145554 its reverse (45554143212), we get a palindrome (66788288766).

The spelling of 21234145554 in words is "twenty-one billion, two hundred thirty-four million, one hundred forty-five thousand, five hundred fifty-four".