78991145 has 8 divisors (see below), whose sum is σ = 95675904. Its totient is φ = 62601904.

The previous prime is 78991141. The next prime is 78991153. The reversal of 78991145 is 54119987.

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 78991145 - 2² = 78991141 is a prime.

It is a super-2 number, since 2×78991145² = 12479201976822050, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 78991096 and 78991105.

It is not an unprimeable number, because it can be changed into a prime (78991141) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 73289 + ... + 74358.

It is an arithmetic number, because the mean of its divisors is an integer number (11959488).

Almost surely, 2^78991145 is an apocalyptic number.

It is an amenable number.

78991145 is a deficient number, since it is larger than the sum of its proper divisors (16684759).

78991145 is a wasteful number, since it uses less digits than its factorization.

78991145 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 147759.

The product of its digits is 90720, while the sum is 44.

The square root of 78991145 is about 8887.6962706879. The cubic root of 78991145 is about 429.0680102926.

The spelling of 78991145 in words is "seventy-eight million, nine hundred ninety-one thousand, one hundred forty-five".