19401216 has 80 divisors (see below), whose sum is σ = 54800064. Its totient is φ = 6078464.

The previous prime is 19401197. The next prime is 19401227. The reversal of 19401216 is 61210491.

It is a Harshad number since it is a multiple of its sum of digits (24).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (5) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 25741 + ... + 26483.

Almost surely, 2^19401216 is an apocalyptic number.

19401216 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 19401216, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (27400032).

19401216 is an abundant number, since it is smaller than the sum of its proper divisors (35398848).

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

19401216 is an equidigital number, since it uses as much as digits as its factorization.

19401216 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 781 (or 765 counting only the distinct ones).

The product of its (nonzero) digits is 432, while the sum is 24.

The square root of 19401216 is about 4404.6811462352. The cubic root of 19401216 is about 268.7053521648.

The spelling of 19401216 in words is "nineteen million, four hundred one thousand, two hundred sixteen".