1641397866 has 8 divisors (see below), whose sum is σ = 3282795744. Its totient is φ = 547132620.

The previous prime is 1641397853. The next prime is 1641397867. The reversal of 1641397866 is 6687931461.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

1641397866 is an admirable number.

It is not an unprimeable number, because it can be changed into a prime (1641397867) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 136783150 + ... + 136783161.

It is an arithmetic number, because the mean of its divisors is an integer number (410349468).

Almost surely, 2^1641397866 is an apocalyptic number.

1641397866 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

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

1641397866 is a wasteful number, since it uses less digits than its factorization.

1641397866 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 273566316.

The product of its digits is 1306368, while the sum is 51.

The square root of 1641397866 is about 40514.1687067623. The cubic root of 1641397866 is about 1179.6086670351.

The spelling of 1641397866 in words is "one billion, six hundred forty-one million, three hundred ninety-seven thousand, eight hundred sixty-six".