1661227008 has 312 divisors, whose sum is σ = 5378538240. Its totient is φ = 454164480.

The previous prime is 1661226991. The next prime is 1661227021. The reversal of 1661227008 is 8007221661.

It is a hoax number, since the sum of its digits (33) coincides with the sum of the digits of its distinct prime factors.

It is a self number, because there is not a number n which added to its sum of digits gives 1661227008.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 18665428 + ... + 18665516.

Almost surely, 2^1661227008 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 1661227008, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2689269120).

1661227008 is an abundant number, since it is smaller than the sum of its proper divisors (3717311232).

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

1661227008 is an equidigital number, since it uses as much as digits as its factorization.

1661227008 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 161 (or 132 counting only the distinct ones).

The product of its (nonzero) digits is 8064, while the sum is 33.

The square root of 1661227008 is about 40758.1526568612. The cubic root of 1661227008 is about 1184.3398099397.

Adding to 1661227008 its reverse (8007221661), we get a palindrome (9668448669).

The spelling of 1661227008 in words is "one billion, six hundred sixty-one million, two hundred twenty-seven thousand, eight".