705428909 has 4 divisors (see below), whose sum is σ = 705494304. Its totient is φ = 705363516.

The previous prime is 705428891. The next prime is 705428951. The reversal of 705428909 is 909824507.

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, and also a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is not a de Polignac number, because 705428909 - 2¹² = 705424813 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 705428909.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (705428309) 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, 12257 + ... + 39510.

It is an arithmetic number, because the mean of its divisors is an integer number (176373576).

Almost surely, 2^705428909 is an apocalyptic number.

It is an amenable number.

705428909 is a deficient number, since it is larger than the sum of its proper divisors (65395).

705428909 is a wasteful number, since it uses less digits than its factorization.

705428909 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 65394.

The product of its (nonzero) digits is 181440, while the sum is 44.

The square root of 705428909 is about 26559.9116903652. The cubic root of 705428909 is about 890.1934978850.

The spelling of 705428909 in words is "seven hundred five million, four hundred twenty-eight thousand, nine hundred nine".