21432764208 has 20 divisors (see below), whose sum is σ = 55367974328. Its totient is φ = 7144254720.

The previous prime is 21432764207. The next prime is 21432764209. The reversal of 21432764208 is 80246723412.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (21432764207) and next prime (21432764209).

It is not an unprimeable number, because it can be changed into a prime (21432764203) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 223257913 + ... + 223258008.

Almost surely, 2^21432764208 is an apocalyptic number.

It is an amenable number.

21432764208 is an abundant number, since it is smaller than the sum of its proper divisors (33935210120).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21432764208 is a wasteful number, since it uses less digits than its factorization.

21432764208 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 446515932 (or 446515926 counting only the distinct ones).

The product of its (nonzero) digits is 129024, while the sum is 39.

The spelling of 21432764208 in words is "twenty-one billion, four hundred thirty-two million, seven hundred sixty-four thousand, two hundred eight".