21870342099 has 12 divisors (see below), whose sum is σ = 32444291776. Its totient is φ = 14186167632.

The previous prime is 21870342073. The next prime is 21870342113. The reversal of 21870342099 is 99024307812.

21870342099 is a `hidden beast` number, since 218 + 7 + 0 + 3 + 420 + 9 + 9 = 666.

It is not a de Polignac number, because 21870342099 - 2¹⁹ = 21869817811 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21870342049) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 32838019 + ... + 32838684.

Almost surely, 2^21870342099 is an apocalyptic number.

21870342099 is a deficient number, since it is larger than the sum of its proper divisors (10573949677).

21870342099 is a wasteful number, since it uses less digits than its factorization.

21870342099 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 65676746 (or 65676743 counting only the distinct ones).

The product of its (nonzero) digits is 217728, while the sum is 45.

The spelling of 21870342099 in words is "twenty-one billion, eight hundred seventy million, three hundred forty-two thousand, ninety-nine".