16121856 has 72 divisors (see below), whose sum is σ = 44040024. Its totient is φ = 5242880.

The previous prime is 16121849. The next prime is 16121857. The reversal of 16121856 is 65812161.

It is an alternating number because its digits alternate between odd and even.

It is a nialpdrome in base 8 and base 16.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (16121857) 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, 393196 + ... + 393236.

It is an arithmetic number, because the mean of its divisors is an integer number (611667).

Almost surely, 2^16121856 is an apocalyptic number.

16121856 is a gapful number since it is divisible by the number (16) 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 16121856, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (22020012).

16121856 is an abundant number, since it is smaller than the sum of its proper divisors (27918168).

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

16121856 is an frugal number, since it uses more digits than its factorization.

16121856 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 78 (or 46 counting only the distinct ones).

The product of its digits is 2880, while the sum is 30.

The square root of 16121856 is about 4015.2031081877. The cubic root of 16121856 is about 252.6222967350.

The spelling of 16121856 in words is "sixteen million, one hundred twenty-one thousand, eight hundred fifty-six".