21099104815 has 8 divisors (see below), whose sum is σ = 25470537120. Its totient is φ = 16778209632.

The previous prime is 21099104791. The next prime is 21099104827. The reversal of 21099104815 is 51840199012.

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 21099104815 - 2⁵ = 21099104783 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 12633360 + ... + 12635029.

It is an arithmetic number, because the mean of its divisors is an integer number (3183817140).

Almost surely, 2^21099104815 is an apocalyptic number.

21099104815 is a deficient number, since it is larger than the sum of its proper divisors (4371432305).

21099104815 is a wasteful number, since it uses less digits than its factorization.

21099104815 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 25268561.

The product of its (nonzero) digits is 25920, while the sum is 40.

The spelling of 21099104815 in words is "twenty-one billion, ninety-nine million, one hundred four thousand, eight hundred fifteen".