21403303994 has 8 divisors (see below), whose sum is σ = 33993482868. Its totient is φ = 10072143040.

The previous prime is 21403303993. The next prime is 21403303997. The reversal of 21403303994 is 49930330412.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 15759538369 + 5643765625 = 125537^2 + 75125^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is not an unprimeable number, because it can be changed into a prime (21403303993) 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, 314754437 + ... + 314754504.

Almost surely, 2^21403303994 is an apocalyptic number.

21403303994 is a deficient number, since it is larger than the sum of its proper divisors (12590178874).

21403303994 is a wasteful number, since it uses less digits than its factorization.

21403303994 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 629508960.

The product of its (nonzero) digits is 69984, while the sum is 38.

The spelling of 21403303994 in words is "twenty-one billion, four hundred three million, three hundred three thousand, nine hundred ninety-four".