78158545 has 8 divisors (see below), whose sum is σ = 95075496. Its totient is φ = 61670016.

The previous prime is 78158513. The next prime is 78158557. The reversal of 78158545 is 54585187.

It can be written as a sum of positive squares in 4 ways, for example, as 14653584 + 63504961 = 3828^2 + 7969^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 78158545 - 2⁵ = 78158513 is a prime.

It is a super-2 number, since 2×78158545² = 12217516313034050, which contains 22 as substring.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 106702 + ... + 107431.

It is an arithmetic number, because the mean of its divisors is an integer number (11884437).

Almost surely, 2^78158545 is an apocalyptic number.

It is an amenable number.

78158545 is a deficient number, since it is larger than the sum of its proper divisors (16916951).

78158545 is a wasteful number, since it uses less digits than its factorization.

78158545 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 214211.

The product of its digits is 224000, while the sum is 43.

The square root of 78158545 is about 8840.7321529385. The cubic root of 78158545 is about 427.5551631334. Note that the first 3 decimals are identical.

The spelling of 78158545 in words is "seventy-eight million, one hundred fifty-eight thousand, five hundred forty-five".