1709379921 has 4 divisors (see below), whose sum is σ = 2279173232. Its totient is φ = 1139586612.

The previous prime is 1709379901. The next prime is 1709379929. The reversal of 1709379921 is 1299739071.

It is a happy number.

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 not a de Polignac number, because 1709379921 - 2⁹ = 1709379409 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1709379929) 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, 284896651 + ... + 284896656.

It is an arithmetic number, because the mean of its divisors is an integer number (569793308).

Almost surely, 2^1709379921 is an apocalyptic number.

It is an amenable number.

1709379921 is a deficient number, since it is larger than the sum of its proper divisors (569793311).

1709379921 is an equidigital number, since it uses as much as digits as its factorization.

1709379921 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 569793310.

The product of its (nonzero) digits is 214326, while the sum is 48.

The square root of 1709379921 is about 41344.6480333307. The cubic root of 1709379921 is about 1195.6742216331.

The spelling of 1709379921 in words is "one billion, seven hundred nine million, three hundred seventy-nine thousand, nine hundred twenty-one".