21406429888 has 14 divisors (see below), whose sum is σ = 42478384436. Its totient is φ = 10703214912.

The previous prime is 21406429879. The next prime is 21406429909. The reversal of 21406429888 is 88892460412.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 167237670 + ... + 167237797.

Almost surely, 2^21406429888 is an apocalyptic number.

It is an amenable number.

21406429888 is a deficient number, since it is larger than the sum of its proper divisors (21071954548).

21406429888 is an equidigital number, since it uses as much as digits as its factorization.

21406429888 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 334475479 (or 334475469 counting only the distinct ones).

The product of its (nonzero) digits is 1769472, while the sum is 52.

The spelling of 21406429888 in words is "twenty-one billion, four hundred six million, four hundred twenty-nine thousand, eight hundred eighty-eight".