78521100851 has 2 divisors, whose sum is σ = 78521100852. Its totient is φ = 78521100850.

The previous prime is 78521100839. The next prime is 78521100863. The reversal of 78521100851 is 15800112587.

It is a balanced prime because it is at equal distance from previous prime (78521100839) and next prime (78521100863).

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-78521100851 is a prime.

It is not a weakly prime, because it can be changed into another prime (78521100451) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 39260550425 + 39260550426.

It is an arithmetic number, because the mean of its divisors is an integer number (39260550426).

Almost surely, 2^78521100851 is an apocalyptic number.

78521100851 is a deficient number, since it is larger than the sum of its proper divisors (1).

78521100851 is an equidigital number, since it uses as much as digits as its factorization.

78521100851 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 22400, while the sum is 38.

The spelling of 78521100851 in words is "seventy-eight billion, five hundred twenty-one million, one hundred thousand, eight hundred fifty-one".