78240169 has 4 divisors (see below), whose sum is σ = 89417344. Its totient is φ = 67062996.

The previous prime is 78240109. The next prime is 78240179. The reversal of 78240169 is 96104287.

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 de Polignac number, because none of the positive numbers 2^k-78240169 is a prime.

It is a super-2 number, since 2×78240169² = 12243048090297122, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (78240109) 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, 5588577 + ... + 5588590.

It is an arithmetic number, because the mean of its divisors is an integer number (22354336).

Almost surely, 2^78240169 is an apocalyptic number.

It is an amenable number.

78240169 is a deficient number, since it is larger than the sum of its proper divisors (11177175).

78240169 is a wasteful number, since it uses less digits than its factorization.

78240169 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11177174.

The product of its (nonzero) digits is 24192, while the sum is 37.

The square root of 78240169 is about 8845.3473080485. The cubic root of 78240169 is about 427.7039488312.

The spelling of 78240169 in words is "seventy-eight million, two hundred forty thousand, one hundred sixty-nine".