1219816 has 32 divisors (see below), whose sum is σ = 2537640. Its totient is φ = 546048.

The previous prime is 1219811. The next prime is 1219831. The reversal of 1219816 is 6189121.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 792100 + 427716 = 890^2 + 654^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1219811) 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, 3690 + ... + 4006.

2^1219816 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1219816, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1268820).

1219816 is an abundant number, since it is smaller than the sum of its proper divisors (1317824).

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

1219816 is a wasteful number, since it uses less digits than its factorization.

1219816 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 373 (or 369 counting only the distinct ones).

The product of its digits is 864, while the sum is 28.

The square root of 1219816 is about 1104.4528056916. The cubic root of 1219816 is about 106.8476009014.

The spelling of 1219816 in words is "one million, two hundred nineteen thousand, eight hundred sixteen".