21454845412 has 324 divisors, whose sum is σ = 53489625588. Its totient is φ = 7495488000.

The previous prime is 21454845409. The next prime is 21454845413.

It is a happy number.

21454845412 is nontrivially palindromic in base 10.

It can be written as a sum of positive squares in 6 ways, for example, as 6071296 + 21448774116 = 2464^2 + 146454^2 .

It is a Smith number, since the sum of its digits (40) coincides with the sum of the digits of its prime factors.

It is not an unprimeable number, because it can be changed into a prime (21454845413) by changing a digit.

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 107 ways as a sum of consecutive naturals, for example, 212424162 + ... + 212424262.

It is an arithmetic number, because the mean of its divisors is an integer number (165091437).

Almost surely, 2^21454845412 is an apocalyptic number.

21454845412 is a gapful number since it is divisible by the number (22) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21454845412, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (26744812794).

21454845412 is an abundant number, since it is smaller than the sum of its proper divisors (32034780176).

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

21454845412 is a wasteful number, since it uses less digits than its factorization.

21454845412 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 220 (or 187 counting only the distinct ones).

The product of its digits is 204800, while the sum is 40.

The spelling of 21454845412 in words is "twenty-one billion, four hundred fifty-four million, eight hundred forty-five thousand, four hundred twelve".