21836561398 has 8 divisors (see below), whose sum is σ = 32784169392. Its totient is φ = 10908504936.

The previous prime is 21836561393. The next prime is 21836561407. The reversal of 21836561398 is 89316563812.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21836561393) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4885090 + ... + 4889557.

It is an arithmetic number, because the mean of its divisors is an integer number (4098021174).

Almost surely, 2^21836561398 is an apocalyptic number.

21836561398 is a deficient number, since it is larger than the sum of its proper divisors (10947607994).

21836561398 is a wasteful number, since it uses less digits than its factorization.

21836561398 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9775766.

The product of its digits is 1866240, while the sum is 52.

The spelling of 21836561398 in words is "twenty-one billion, eight hundred thirty-six million, five hundred sixty-one thousand, three hundred ninety-eight".