21123541545400 has 144 divisors (see below), whose sum is σ = 59614495968240. Its totient is φ = 6927471936000.

The previous prime is 21123541545391. The next prime is 21123541545487. The reversal of 21123541545400 is 454514532112.

It is a super-2 number, since 2×21123541545400² (a number of 27 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 21123541545400.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 46632501 + ... + 47083300.

It is an arithmetic number, because the mean of its divisors is an integer number (413989555335).

Almost surely, 2^{21123541545400} is an apocalyptic number.

21123541545400 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21123541545400 is an abundant number, since it is smaller than the sum of its proper divisors (38490954422840).

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

21123541545400 is a wasteful number, since it uses less digits than its factorization.

21123541545400 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 93715854 (or 93715838 counting only the distinct ones).

The product of its (nonzero) digits is 96000, while the sum is 37.

The spelling of 21123541545400 in words is "twenty-one trillion, one hundred twenty-three billion, five hundred forty-one million, five hundred forty-five thousand, four hundred".