97878889 has 4 divisors (see below), whose sum is σ = 98093524. Its totient is φ = 97664256.

The previous prime is 97878883. The next prime is 97878901. The reversal of 97878889 is 98887879.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 98887879 = 23 ⋅4299473.

It can be written as a sum of positive squares in 2 ways, for example, as 85747600 + 12131289 = 9260^2 + 3483^2 .

It is a cyclic number.

It is not a de Polignac number, because 97878889 - 2⁷ = 97878761 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 97878889.

It is not an unprimeable number, because it can be changed into a prime (97878883) 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, 106632 + ... + 107545.

It is an arithmetic number, because the mean of its divisors is an integer number (24523381).

Almost surely, 2^97878889 is an apocalyptic number.

It is an amenable number.

97878889 is a deficient number, since it is larger than the sum of its proper divisors (214635).

97878889 is a wasteful number, since it uses less digits than its factorization.

97878889 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 214634.

The product of its digits is 16257024, while the sum is 64.

The square root of 97878889 is about 9893.3760163051. The cubic root of 97878889 is about 460.8536275984.

The spelling of 97878889 in words is "ninety-seven million, eight hundred seventy-eight thousand, eight hundred eighty-nine".