1705921813 has 4 divisors (see below), whose sum is σ = 1727515840. Its totient is φ = 1684327788.

The previous prime is 1705921801. The next prime is 1705921817. The reversal of 1705921813 is 3181295071.

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 not a de Polignac number, because 1705921813 - 2¹⁷ = 1705790741 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1705921817) 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, 10796895 + ... + 10797052.

It is an arithmetic number, because the mean of its divisors is an integer number (431878960).

Almost surely, 2^1705921813 is an apocalyptic number.

It is an amenable number.

1705921813 is a deficient number, since it is larger than the sum of its proper divisors (21594027).

1705921813 is an equidigital number, since it uses as much as digits as its factorization.

1705921813 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 21594026.

The product of its (nonzero) digits is 15120, while the sum is 37.

The square root of 1705921813 is about 41302.8063574377. The cubic root of 1705921813 is about 1194.8673867651.

The spelling of 1705921813 in words is "one billion, seven hundred five million, nine hundred twenty-one thousand, eight hundred thirteen".