78489009 has 24 divisors (see below), whose sum is σ = 116093952. Its totient is φ = 51085440.

The previous prime is 78489007. The next prime is 78489023. The reversal of 78489009 is 90098487.

It is not a de Polignac number, because 78489009 - 2¹ = 78489007 is a prime.

It is not an unprimeable number, because it can be changed into a prime (78489001) 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, 71664 + ... + 72750.

It is an arithmetic number, because the mean of its divisors is an integer number (4837248).

Almost surely, 2^78489009 is an apocalyptic number.

It is an amenable number.

78489009 is a deficient number, since it is larger than the sum of its proper divisors (37604943).

78489009 is a wasteful number, since it uses less digits than its factorization.

78489009 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1277 (or 1274 counting only the distinct ones).

The product of its (nonzero) digits is 145152, while the sum is 45.

The square root of 78489009 is about 8859.4022936088. The cubic root of 78489009 is about 428.1569012334.

The spelling of 78489009 in words is "seventy-eight million, four hundred eighty-nine thousand, nine".