21564242064141 has 64 divisors (see below), whose sum is σ = 34646528716800. Its totient is φ = 11654556950016.

The previous prime is 21564242064121. The next prime is 21564242064187. The reversal of 21564242064141 is 14146024246512.

It is a happy number.

It is not a de Polignac number, because 21564242064141 - 2⁹ = 21564242063629 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21564242064093 and 21564242064102.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21564242064121) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 1256722120 + ... + 1256739278.

It is an arithmetic number, because the mean of its divisors is an integer number (541352011200).

Almost surely, 2^{21564242064141} is an apocalyptic number.

21564242064141 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

It is an amenable number.

21564242064141 is a deficient number, since it is larger than the sum of its proper divisors (13082286652659).

21564242064141 is a wasteful number, since it uses less digits than its factorization.

21564242064141 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 22218.

The product of its (nonzero) digits is 368640, while the sum is 42.

The spelling of 21564242064141 in words is "twenty-one trillion, five hundred sixty-four billion, two hundred forty-two million, sixty-four thousand, one hundred forty-one".