128456654821 has 32 divisors (see below), whose sum is σ = 150334341120. Its totient is φ = 108469267200.

The previous prime is 128456654791. The next prime is 128456654869.

128456654821 is nontrivially palindromic in base 10.

It is a cyclic number.

It is not a de Polignac number, because 128456654821 - 2¹³ = 128456646629 is a prime.

It is a super-2 number, since 2×128456654821² (a number of 23 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (128456658821) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 4521900 + ... + 4550218.

It is an arithmetic number, because the mean of its divisors is an integer number (4697948160).

Almost surely, 2^128456654821 is an apocalyptic number.

128456654821 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

128456654821 is a deficient number, since it is larger than the sum of its proper divisors (21877686299).

128456654821 is a wasteful number, since it uses less digits than its factorization.

128456654821 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 28665.

The product of its digits is 3686400, while the sum is 52.

It can be divided in two parts, 12845 and 6654821, that added together give a palindrome (6667666).

The spelling of 128456654821 in words is "one hundred twenty-eight billion, four hundred fifty-six million, six hundred fifty-four thousand, eight hundred twenty-one".