78098989 has 4 divisors (see below), whose sum is σ = 78256000. Its totient is φ = 77941980.

The previous prime is 78098981. The next prime is 78099011. The reversal of 78098989 is 98989087.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 78098989 - 2³ = 78098981 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 (78098981) 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, 77757 + ... + 78754.

It is an arithmetic number, because the mean of its divisors is an integer number (19564000).

Almost surely, 2^78098989 is an apocalyptic number.

It is an amenable number.

78098989 is a deficient number, since it is larger than the sum of its proper divisors (157011).

78098989 is a wasteful number, since it uses less digits than its factorization.

78098989 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 157010.

The product of its (nonzero) digits is 2612736, while the sum is 58.

The square root of 78098989 is about 8837.3632379800. The cubic root of 78098989 is about 427.4465380063.

The spelling of 78098989 in words is "seventy-eight million, ninety-eight thousand, nine hundred eighty-nine".