78140705 has 4 divisors (see below), whose sum is σ = 93768852. Its totient is φ = 62512560.

The previous prime is 78140701. The next prime is 78140723. The reversal of 78140705 is 50704187.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 50704187 = 59 ⋅859393.

It can be written as a sum of positive squares in 2 ways, for example, as 32672656 + 45468049 = 5716^2 + 6743^2 .

It is not a de Polignac number, because 78140705 - 2² = 78140701 is a prime.

It is a super-2 number, since 2×78140705² = 12211939555794050, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (78140701) 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, 7814066 + ... + 7814075.

It is an arithmetic number, because the mean of its divisors is an integer number (23442213).

Almost surely, 2^78140705 is an apocalyptic number.

It is an amenable number.

78140705 is a deficient number, since it is larger than the sum of its proper divisors (15628147).

78140705 is a wasteful number, since it uses less digits than its factorization.

78140705 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15628146.

The product of its (nonzero) digits is 7840, while the sum is 32.

The square root of 78140705 is about 8839.7231291483. The cubic root of 78140705 is about 427.5226302670.

The spelling of 78140705 in words is "seventy-eight million, one hundred forty thousand, seven hundred five".