16420971257928 has 128 divisors (see below), whose sum is σ = 46478124000000. Its totient is φ = 5369955641856.

The previous prime is 16420971257917. The next prime is 16420971257939. The reversal of 16420971257928 is 82975217902461.

16420971257928 is a `hidden beast` number, since 1 + 6 + 4 + 20 + 9 + 7 + 12 + 579 + 28 = 666.

It is an interprime number because it is at equal distance from previous prime (16420971257917) and next prime (16420971257939).

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 165820573 + ... + 165919571.

It is an arithmetic number, because the mean of its divisors is an integer number (363110343750).

Almost surely, 2^{16420971257928} is an apocalyptic number.

16420971257928 is a gapful number since it is divisible by the number (18) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 16420971257928, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (23239062000000).

16420971257928 is an abundant number, since it is smaller than the sum of its proper divisors (30057152742072).

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

16420971257928 is a wasteful number, since it uses less digits than its factorization.

16420971257928 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 113556 (or 113546 counting only the distinct ones).

The product of its (nonzero) digits is 30481920, while the sum is 63.

The spelling of 16420971257928 in words is "sixteen trillion, four hundred twenty billion, nine hundred seventy-one million, two hundred fifty-seven thousand, nine hundred twenty-eight".