1243405099 has 4 divisors (see below), whose sum is σ = 1243900840. Its totient is φ = 1242909360.

The previous prime is 1243405081. The next prime is 1243405103. The reversal of 1243405099 is 9905043421.

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 1243405099 - 2⁵ = 1243405067 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1243405699) 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, 244089 + ... + 249130.

It is an arithmetic number, because the mean of its divisors is an integer number (310975210).

Almost surely, 2^1243405099 is an apocalyptic number.

1243405099 is a deficient number, since it is larger than the sum of its proper divisors (495741).

1243405099 is an equidigital number, since it uses as much as digits as its factorization.

1243405099 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 495740.

The product of its (nonzero) digits is 38880, while the sum is 37.

The square root of 1243405099 is about 35261.9497333883. The cubic root of 1243405099 is about 1075.3195657827.

The spelling of 1243405099 in words is "one billion, two hundred forty-three million, four hundred five thousand, ninety-nine".