16721509438 has 8 divisors (see below), whose sum is σ = 25082862480. Its totient is φ = 8360555280.

The previous prime is 16721509421. The next prime is 16721509439. The reversal of 16721509438 is 83490512761.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (16721509439) 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, 50103 + ... + 189613.

It is an arithmetic number, because the mean of its divisors is an integer number (3135357810).

It is a 1-persistent number, because it is pandigital, but 2⋅16721509438 = 33443018876 is not.

Almost surely, 2^16721509438 is an apocalyptic number.

16721509438 is a deficient number, since it is larger than the sum of its proper divisors (8361353042).

16721509438 is a wasteful number, since it uses less digits than its factorization.

16721509438 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 199442.

The product of its (nonzero) digits is 362880, while the sum is 46.

The spelling of 16721509438 in words is "sixteen billion, seven hundred twenty-one million, five hundred nine thousand, four hundred thirty-eight".