897153821 has 4 divisors (see below), whose sum is σ = 905384700. Its totient is φ = 888922944.

The previous prime is 897153809. The next prime is 897153827. The reversal of 897153821 is 128351798.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 128351798 = 2 ⋅64175899.

It can be written as a sum of positive squares in 2 ways, for example, as 614544100 + 282609721 = 24790^2 + 16811^2 .

It is a cyclic number.

It is not a de Polignac number, because 897153821 - 2⁶ = 897153757 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (897153827) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4115276 + ... + 4115493.

It is an arithmetic number, because the mean of its divisors is an integer number (226346175).

Almost surely, 2^897153821 is an apocalyptic number.

It is an amenable number.

897153821 is a deficient number, since it is larger than the sum of its proper divisors (8230879).

897153821 is a wasteful number, since it uses less digits than its factorization.

897153821 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8230878.

The product of its digits is 120960, while the sum is 44.

The square root of 897153821 is about 29952.5261205128. The cubic root of 897153821 is about 964.4705485159.

The spelling of 897153821 in words is "eight hundred ninety-seven million, one hundred fifty-three thousand, eight hundred twenty-one".