154405123321 has 4 divisors (see below), whose sum is σ = 163487777652. Its totient is φ = 145322468992.

The previous prime is 154405123291. The next prime is 154405123343. The reversal of 154405123321 is 123321504451.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 120800734096 + 33604389225 = 347564^2 + 183315^2 .

It is a cyclic number.

It is not a de Polignac number, because 154405123321 - 2¹⁹ = 154404599033 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (154405123921) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4541327140 + ... + 4541327173.

It is an arithmetic number, because the mean of its divisors is an integer number (40871944413).

Almost surely, 2^154405123321 is an apocalyptic number.

It is an amenable number.

154405123321 is a deficient number, since it is larger than the sum of its proper divisors (9082654331).

154405123321 is an equidigital number, since it uses as much as digits as its factorization.

154405123321 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9082654330.

The product of its (nonzero) digits is 14400, while the sum is 31.

Adding to 154405123321 its reverse (123321504451), we get a palindrome (277726627772).

The spelling of 154405123321 in words is "one hundred fifty-four billion, four hundred five million, one hundred twenty-three thousand, three hundred twenty-one".