43421320999 has 16 divisors (see below), whose sum is σ = 51343557120. Its totient is φ = 35929283040.

The previous prime is 43421320997. The next prime is 43421321003. The reversal of 43421320999 is 99902312434.

It is a happy number.

It is not a de Polignac number, because 43421320999 - 2¹ = 43421320997 is a prime.

It is a super-2 number, since 2×43421320999² (a number of 22 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (43421320997) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1746244 + ... + 1770934.

It is an arithmetic number, because the mean of its divisors is an integer number (3208972320).

Almost surely, 2^43421320999 is an apocalyptic number.

43421320999 is a deficient number, since it is larger than the sum of its proper divisors (7922236121).

43421320999 is a wasteful number, since it uses less digits than its factorization.

43421320999 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 33390.

The product of its (nonzero) digits is 419904, while the sum is 46.

The spelling of 43421320999 in words is "forty-three billion, four hundred twenty-one million, three hundred twenty thousand, nine hundred ninety-nine".