78643011 has 4 divisors (see below), whose sum is σ = 104857352. Its totient is φ = 52428672.

The previous prime is 78643007. The next prime is 78643013. The reversal of 78643011 is 11034687.

It is a happy number.

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

It is not a de Polignac number, because 78643011 - 2² = 78643007 is a prime.

It is a super-2 number, since 2×78643011² = 12369446358292242, which contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 78643011.

It is not an unprimeable number, because it can be changed into a prime (78643013) 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, 13107166 + ... + 13107171.

It is an arithmetic number, because the mean of its divisors is an integer number (26214338).

Almost surely, 2^78643011 is an apocalyptic number.

78643011 is a deficient number, since it is larger than the sum of its proper divisors (26214341).

78643011 is a wasteful number, since it uses less digits than its factorization.

78643011 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 26214340.

The product of its (nonzero) digits is 4032, while the sum is 30.

The square root of 78643011 is about 8868.0894785743. The cubic root of 78643011 is about 428.4367448372.

Adding to 78643011 its reverse (11034687), we get a palindrome (89677698).

The spelling of 78643011 in words is "seventy-eight million, six hundred forty-three thousand, eleven".