21234130399 has 4 divisors (see below), whose sum is σ = 21234575560. Its totient is φ = 21233685240.

The previous prime is 21234130343. The next prime is 21234130459. The reversal of 21234130399 is 99303143212.

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 21234130399 - 2¹¹ = 21234128351 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21234130319) 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, 141084 + ... + 249745.

It is an arithmetic number, because the mean of its divisors is an integer number (5308643890).

Almost surely, 2^21234130399 is an apocalyptic number.

21234130399 is a deficient number, since it is larger than the sum of its proper divisors (445161).

21234130399 is an equidigital number, since it uses as much as digits as its factorization.

21234130399 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 445160.

The product of its (nonzero) digits is 34992, while the sum is 37.

The spelling of 21234130399 in words is "twenty-one billion, two hundred thirty-four million, one hundred thirty thousand, three hundred ninety-nine".