97821857 has 16 divisors (see below), whose sum is σ = 114314112. Its totient is φ = 81976320.

The previous prime is 97821839. The next prime is 97821869. The reversal of 97821857 is 75812879.

It is a cyclic number.

It is not a de Polignac number, because 97821857 - 2⁶ = 97821793 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (97821817) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 81818 + ... + 83004.

It is an arithmetic number, because the mean of its divisors is an integer number (7144632).

Almost surely, 2^97821857 is an apocalyptic number.

It is an amenable number.

97821857 is a deficient number, since it is larger than the sum of its proper divisors (16492255).

97821857 is a wasteful number, since it uses less digits than its factorization.

97821857 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1448.

The product of its digits is 282240, while the sum is 47.

The square root of 97821857 is about 9890.4932637356. The cubic root of 97821857 is about 460.7641002552.

The spelling of 97821857 in words is "ninety-seven million, eight hundred twenty-one thousand, eight hundred fifty-seven".