647697 has 4 divisors (see below), whose sum is σ = 863600. Its totient is φ = 431796.

The previous prime is 647693. The next prime is 647719. The reversal of 647697 is 796746.

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 647697 - 2² = 647693 is a prime.

It is a super-2 number, since 2×647697² = 839022807618, which contains 22 as substring.

It is a D-number.

It is a Duffinian number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 647697.

It is not an unprimeable number, because it can be changed into a prime (647693) 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, 107947 + ... + 107952.

It is an arithmetic number, because the mean of its divisors is an integer number (215900).

2⁶⁴⁷⁶⁹⁷ is an apocalyptic number.

It is an amenable number.

647697 is a deficient number, since it is larger than the sum of its proper divisors (215903).

647697 is a wasteful number, since it uses less digits than its factorization.

647697 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 215902.

The product of its digits is 63504, while the sum is 39.

The square root of 647697 is about 804.7962475062. The cubic root of 647697 is about 86.5214844113.

The spelling of 647697 in words is "six hundred forty-seven thousand, six hundred ninety-seven".