21621544230045 has 32 divisors (see below), whose sum is σ = 34695389975040. Its totient is φ = 11497852869440.

The previous prime is 21621544230029. The next prime is 21621544230059. The reversal of 21621544230045 is 54003244512612.

It is not a de Polignac number, because 21621544230045 - 2⁴ = 21621544230029 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21621544229985 and 21621544230012.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 200125090 + ... + 200233100.

It is an arithmetic number, because the mean of its divisors is an integer number (1084230936720).

Almost surely, 2^{21621544230045} is an apocalyptic number.

It is an amenable number.

21621544230045 is a deficient number, since it is larger than the sum of its proper divisors (13073845744995).

21621544230045 is a wasteful number, since it uses less digits than its factorization.

21621544230045 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 146825.

The product of its (nonzero) digits is 230400, while the sum is 39.

Adding to 21621544230045 its reverse (54003244512612), we get a palindrome (75624788742657).

The spelling of 21621544230045 in words is "twenty-one trillion, six hundred twenty-one billion, five hundred forty-four million, two hundred thirty thousand, forty-five".