19650816 has 72 divisors (see below), whose sum is σ = 58131360. Its totient is φ = 6547968.

The previous prime is 19650803. The next prime is 19650817. The reversal of 19650816 is 61805691.

It is a tau number, because it is divible by the number of its divisors (72).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is not an unprimeable number, because it can be changed into a prime (19650817) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 5491 + ... + 8333.

It is an arithmetic number, because the mean of its divisors is an integer number (807380).

Almost surely, 2^19650816 is an apocalyptic number.

19650816 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 19650816, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (29065680).

19650816 is an abundant number, since it is smaller than the sum of its proper divisors (38480544).

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

19650816 is an equidigital number, since it uses as much as digits as its factorization.

19650816 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2868 (or 2848 counting only the distinct ones).

The product of its (nonzero) digits is 12960, while the sum is 36.

The square root of 19650816 is about 4432.9240913871. The cubic root of 19650816 is about 269.8527592250.

The spelling of 19650816 in words is "nineteen million, six hundred fifty thousand, eight hundred sixteen".