21120144999 has 16 divisors (see below), whose sum is σ = 28347656832. Its totient is φ = 13986507488.

The previous prime is 21120144961. The next prime is 21120145003. The reversal of 21120144999 is 99944102112.

It is a cyclic number.

It is not a de Polignac number, because 21120144999 - 2¹⁷ = 21120013927 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 21120144999.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21120144949) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 598912 + ... + 633194.

It is an arithmetic number, because the mean of its divisors is an integer number (1771728552).

Almost surely, 2^21120144999 is an apocalyptic number.

21120144999 is a deficient number, since it is larger than the sum of its proper divisors (7227511833).

21120144999 is a wasteful number, since it uses less digits than its factorization.

21120144999 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 35646.

The product of its (nonzero) digits is 46656, while the sum is 42.

The spelling of 21120144999 in words is "twenty-one billion, one hundred twenty million, one hundred forty-four thousand, nine hundred ninety-nine".