897720647 has 4 divisors (see below), whose sum is σ = 897780840. Its totient is φ = 897660456.

The previous prime is 897720643. The next prime is 897720653. The reversal of 897720647 is 746027798.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length, and also an emirpimes, since its reverse is a distinct semiprime: 746027798 = 2 ⋅373013899.

It is a cyclic number.

It is not a de Polignac number, because 897720647 - 2² = 897720643 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 897720595 and 897720604.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (897720643) 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, 10793 + ... + 43725.

It is an arithmetic number, because the mean of its divisors is an integer number (224445210).

Almost surely, 2^897720647 is an apocalyptic number.

897720647 is a deficient number, since it is larger than the sum of its proper divisors (60193).

897720647 is a wasteful number, since it uses less digits than its factorization.

897720647 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 60192.

The product of its (nonzero) digits is 1185408, while the sum is 50.

The square root of 897720647 is about 29961.9866998168. The cubic root of 897720647 is about 964.6736247620.

The spelling of 897720647 in words is "eight hundred ninety-seven million, seven hundred twenty thousand, six hundred forty-seven".