78197489 has 4 divisors (see below), whose sum is σ = 78234480. Its totient is φ = 78160500.

The previous prime is 78197477. The next prime is 78197503. The reversal of 78197489 is 98479187.

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, and also an emirpimes, since its reverse is a distinct semiprime: 98479187 = 2713 ⋅36299.

It is a cyclic number.

It is not a de Polignac number, because 78197489 - 2⁴ = 78197473 is a prime.

It is a super-2 number, since 2×78197489² = 12229694571810242, which contains 22 as substring.

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 78197489.

It is not an unprimeable number, because it can be changed into a prime (78197429) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 15119 + ... + 19620.

It is an arithmetic number, because the mean of its divisors is an integer number (19558620).

Almost surely, 2^78197489 is an apocalyptic number.

It is an amenable number.

78197489 is a deficient number, since it is larger than the sum of its proper divisors (36991).

78197489 is a wasteful number, since it uses less digits than its factorization.

78197489 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 36990.

The product of its digits is 1016064, while the sum is 53.

The square root of 78197489 is about 8842.9344111556. The cubic root of 78197489 is about 427.6261638731.

The spelling of 78197489 in words is "seventy-eight million, one hundred ninety-seven thousand, four hundred eighty-nine".