78140217 has 16 divisors (see below), whose sum is σ = 109901120. Its totient is φ = 49248000.

The previous prime is 78140213. The next prime is 78140221. The reversal of 78140217 is 71204187.

It is an interprime number because it is at equal distance from previous prime (78140213) and next prime (78140221).

It is not a de Polignac number, because 78140217 - 2² = 78140213 is a prime.

It is a super-2 number, since 2×78140217² = 12211787025614178, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (78140213) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 33117 + ... + 35397.

It is an arithmetic number, because the mean of its divisors is an integer number (6868820).

Almost surely, 2^78140217 is an apocalyptic number.

It is an amenable number.

78140217 is a deficient number, since it is larger than the sum of its proper divisors (31760903).

78140217 is a wasteful number, since it uses less digits than its factorization.

78140217 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2904.

The product of its (nonzero) digits is 3136, while the sum is 30.

The square root of 78140217 is about 8839.6955264308. The cubic root of 78140217 is about 427.5217402849.

The spelling of 78140217 in words is "seventy-eight million, one hundred forty thousand, two hundred seventeen".