78409601 has 4 divisors (see below), whose sum is σ = 78432852. Its totient is φ = 78386352.

The previous prime is 78409577. The next prime is 78409607. The reversal of 78409601 is 10690487.

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

It can be written as a sum of positive squares in 2 ways, for example, as 14025025 + 64384576 = 3745^2 + 8024^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-78409601 is a prime.

It is a super-2 number, since 2×78409601² = 12296131057958402, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (78409607) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 5486 + ... + 13671.

It is an arithmetic number, because the mean of its divisors is an integer number (19608213).

Almost surely, 2^78409601 is an apocalyptic number.

It is an amenable number.

78409601 is a deficient number, since it is larger than the sum of its proper divisors (23251).

78409601 is a wasteful number, since it uses less digits than its factorization.

78409601 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 23250.

The product of its (nonzero) digits is 12096, while the sum is 35.

The square root of 78409601 is about 8854.9195930850. The cubic root of 78409601 is about 428.0124625160.

The spelling of 78409601 in words is "seventy-eight million, four hundred nine thousand, six hundred one".