23216281821 has 24 divisors (see below), whose sum is σ = 34259846400. Its totient is φ = 15143031456.

The previous prime is 23216281819. The next prime is 23216281831. The reversal of 23216281821 is 12818261232.

It is a happy number.

23216281821 is a `hidden beast` number, since 2 + 3 + 2 + 1 + 628 + 1 + 8 + 21 = 666.

It is not a de Polignac number, because 23216281821 - 2¹ = 23216281819 is a prime.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (23216281831) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 1524955 + ... + 1540103.

It is an arithmetic number, because the mean of its divisors is an integer number (1427493600).

Almost surely, 2^23216281821 is an apocalyptic number.

It is an amenable number.

23216281821 is a deficient number, since it is larger than the sum of its proper divisors (11043564579).

23216281821 is a wasteful number, since it uses less digits than its factorization.

23216281821 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 18825 (or 18822 counting only the distinct ones).

The product of its digits is 18432, while the sum is 36.

The spelling of 23216281821 in words is "twenty-three billion, two hundred sixteen million, two hundred eighty-one thousand, eight hundred twenty-one".