1641279816 has 144 divisors (see below), whose sum is σ = 5099028480. Its totient is φ = 475675200.

The previous prime is 1641279799. The next prime is 1641279851. The reversal of 1641279816 is 6189721461.

It is an unprimeable number.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 196281 + ... + 204471.

It is an arithmetic number, because the mean of its divisors is an integer number (35409920).

Almost surely, 2^1641279816 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 1641279816, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2549514240).

1641279816 is an abundant number, since it is smaller than the sum of its proper divisors (3457748664).

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

1641279816 is a wasteful number, since it uses less digits than its factorization.

1641279816 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8248 (or 8230 counting only the distinct ones).

The product of its digits is 145152, while the sum is 45.

The square root of 1641279816 is about 40512.7117828466. The cubic root of 1641279816 is about 1179.5803870459.

The spelling of 1641279816 in words is "one billion, six hundred forty-one million, two hundred seventy-nine thousand, eight hundred sixteen".