21099599569 has 8 divisors (see below), whose sum is σ = 21356778240. Its totient is φ = 20842491696.

The previous prime is 21099599531. The next prime is 21099599593. The reversal of 21099599569 is 96599599012.

It is a happy number.

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

It is a cyclic number.

It is not a de Polignac number, because 21099599569 - 2¹¹ = 21099597521 is a prime.

It is a super-2 number, since 2×21099599569² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 21099599569.

It is not an unprimeable number, because it can be changed into a prime (21099599509) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 823104 + ... + 848350.

It is an arithmetic number, because the mean of its divisors is an integer number (2669597280).

Almost surely, 2^21099599569 is an apocalyptic number.

It is an amenable number.

21099599569 is a deficient number, since it is larger than the sum of its proper divisors (257178671).

21099599569 is a wasteful number, since it uses less digits than its factorization.

21099599569 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 35399.

The product of its (nonzero) digits is 17714700, while the sum is 64.

The spelling of 21099599569 in words is "twenty-one billion, ninety-nine million, five hundred ninety-nine thousand, five hundred sixty-nine".