1641405817 has 4 divisors (see below), whose sum is σ = 1642217616. Its totient is φ = 1640594020.

The previous prime is 1641405797. The next prime is 1641405827. The reversal of 1641405817 is 7185041461.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1641405817 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1641405827) 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 3 ways as a sum of consecutive naturals, for example, 402859 + ... + 406912.

It is an arithmetic number, because the mean of its divisors is an integer number (410554404).

Almost surely, 2^1641405817 is an apocalyptic number.

It is an amenable number.

1641405817 is a deficient number, since it is larger than the sum of its proper divisors (811799).

1641405817 is an equidigital number, since it uses as much as digits as its factorization.

1641405817 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 811798.

The product of its (nonzero) digits is 26880, while the sum is 37.

The square root of 1641405817 is about 40514.2668328084. The cubic root of 1641405817 is about 1179.6105717233.

The spelling of 1641405817 in words is "one billion, six hundred forty-one million, four hundred five thousand, eight hundred seventeen".