78516001 has 4 divisors (see below), whose sum is σ = 78566292. Its totient is φ = 78465712.

The previous prime is 78515981. The next prime is 78516007. The reversal of 78516001 is 10061587.

It is a happy number.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 46253601 + 32262400 = 6801^2 + 5680^2 .

It is a cyclic number.

It is not a de Polignac number, because 78516001 - 2⁷ = 78515873 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (78516007) 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, 22726 + ... + 25951.

It is an arithmetic number, because the mean of its divisors is an integer number (19641573).

Almost surely, 2^78516001 is an apocalyptic number.

It is an amenable number.

78516001 is a deficient number, since it is larger than the sum of its proper divisors (50291).

78516001 is a wasteful number, since it uses less digits than its factorization.

78516001 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 50290.

The product of its (nonzero) digits is 1680, while the sum is 28.

The square root of 78516001 is about 8860.9255159944. The cubic root of 78516001 is about 428.2059759880.

Adding to 78516001 its reverse (10061587), we get a palindrome (88577588).

The spelling of 78516001 in words is "seventy-eight million, five hundred sixteen thousand, one".