1641340781 has 8 divisors (see below), whose sum is σ = 1646919744. Its totient is φ = 1635772320.

The previous prime is 1641340751. The next prime is 1641340793. The reversal of 1641340781 is 1870431461.

It is a happy number.

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

It is a cyclic number.

It is not a de Polignac number, because 1641340781 - 2⁶ = 1641340717 is a prime.

It is a super-2 number, since 2×1641340781² = 5387999118747379922, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1641340751) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 414296 + ... + 418238.

It is an arithmetic number, because the mean of its divisors is an integer number (205864968).

Almost surely, 2^1641340781 is an apocalyptic number.

It is an amenable number.

1641340781 is a deficient number, since it is larger than the sum of its proper divisors (5578963).

1641340781 is an equidigital number, since it uses as much as digits as its factorization.

1641340781 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5251.

The product of its (nonzero) digits is 16128, while the sum is 35.

The square root of 1641340781 is about 40513.4641940183. The cubic root of 1641340781 is about 1179.5949919551.

The spelling of 1641340781 in words is "one billion, six hundred forty-one million, three hundred forty thousand, seven hundred eighty-one".