898784721 has 32 divisors (see below), whose sum is σ = 1403788800. Its totient is φ = 566773200.

The previous prime is 898784633. The next prime is 898784827. The reversal of 898784721 is 127487898.

898784721 = 3291² + 3292² + ... + 3371².

It is a happy number.

It is a de Polignac number, because none of the positive numbers 2^k-898784721 is a prime.

It is not an unprimeable number, because it can be changed into a prime (898784021) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 538330 + ... + 539996.

It is an arithmetic number, because the mean of its divisors is an integer number (43868400).

Almost surely, 2^898784721 is an apocalyptic number.

It is an amenable number.

898784721 is a deficient number, since it is larger than the sum of its proper divisors (505004079).

898784721 is a wasteful number, since it uses less digits than its factorization.

898784721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2746 (or 2740 counting only the distinct ones).

The product of its digits is 1806336, while the sum is 54.

The square root of 898784721 is about 29979.7385078656. The cubic root of 898784721 is about 965.0546188671.

The spelling of 898784721 in words is "eight hundred ninety-eight million, seven hundred eighty-four thousand, seven hundred twenty-one".