78642851 has 8 divisors (see below), whose sum is σ = 89931360. Its totient is φ = 67367808.

The previous prime is 78642779. The next prime is 78642853. The reversal of 78642851 is 15824687.

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 78642851 - 2²² = 74448547 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 78642799 and 78642808.

It is not an unprimeable number, because it can be changed into a prime (78642853) 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, 19805 + ... + 23441.

It is an arithmetic number, because the mean of its divisors is an integer number (11241420).

Almost surely, 2^78642851 is an apocalyptic number.

78642851 is a deficient number, since it is larger than the sum of its proper divisors (11288509).

78642851 is a wasteful number, since it uses less digits than its factorization.

78642851 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6733.

The product of its digits is 107520, while the sum is 41.

The square root of 78642851 is about 8868.0804574609. The cubic root of 78642851 is about 428.4364542840.

The spelling of 78642851 in words is "seventy-eight million, six hundred forty-two thousand, eight hundred fifty-one".