21030400099 has 4 divisors (see below), whose sum is σ = 21044698240. Its totient is φ = 21016101960.

The previous prime is 21030400073. The next prime is 21030400109. The reversal of 21030400099 is 99000403012.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 21030400099 - 2²⁹ = 20493529187 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21030400019) 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, 7146864 + ... + 7149805.

It is an arithmetic number, because the mean of its divisors is an integer number (5261174560).

Almost surely, 2^21030400099 is an apocalyptic number.

21030400099 is a deficient number, since it is larger than the sum of its proper divisors (14298141).

21030400099 is a wasteful number, since it uses less digits than its factorization.

21030400099 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 14298140.

The product of its (nonzero) digits is 1944, while the sum is 28.

The spelling of 21030400099 in words is "twenty-one billion, thirty million, four hundred thousand, ninety-nine".