78501979 has 2 divisors, whose sum is σ = 78501980. Its totient is φ = 78501978.

The previous prime is 78501949. The next prime is 78501989. The reversal of 78501979 is 97910587.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 78501979 - 2¹³ = 78493787 is a prime.

It is not a weakly prime, because it can be changed into another prime (78501949) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 39250989 + 39250990.

It is an arithmetic number, because the mean of its divisors is an integer number (39250990).

Almost surely, 2^78501979 is an apocalyptic number.

78501979 is a deficient number, since it is larger than the sum of its proper divisors (1).

78501979 is an equidigital number, since it uses as much as digits as its factorization.

78501979 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 158760, while the sum is 46.

The square root of 78501979 is about 8860.1342540618. The cubic root of 78501979 is about 428.1804836824.

The spelling of 78501979 in words is "seventy-eight million, five hundred one thousand, nine hundred seventy-nine".