97540209 has 24 divisors (see below), whose sum is σ = 152657960. Its totient is φ = 60012576.

The previous prime is 97540199. The next prime is 97540213. The reversal of 97540209 is 90204579.

97540209 is a `hidden beast` number, since 97 + 540 + 20 + 9 = 666.

It can be written as a sum of positive squares in 4 ways, for example, as 38787984 + 58752225 = 6228^2 + 7665^2 .

It is not a de Polignac number, because 97540209 - 2⁷ = 97540081 is a prime.

It is not an unprimeable number, because it can be changed into a prime (97540109) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 17307 + ... + 22239.

Almost surely, 2^97540209 is an apocalyptic number.

It is an amenable number.

97540209 is a deficient number, since it is larger than the sum of its proper divisors (55117751).

97540209 is a wasteful number, since it uses less digits than its factorization.

97540209 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4978 (or 4949 counting only the distinct ones).

The product of its (nonzero) digits is 22680, while the sum is 36.

The square root of 97540209 is about 9876.2446810516. The cubic root of 97540209 is about 460.3214655914.

The spelling of 97540209 in words is "ninety-seven million, five hundred forty thousand, two hundred nine".