78802081 has 4 divisors (see below), whose sum is σ = 78923412. Its totient is φ = 78680752.

The previous prime is 78802067. The next prime is 78802099. The reversal of 78802081 is 18020887.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 18020887 = 37 ⋅487051.

It can be written as a sum of positive squares in 2 ways, for example, as 51969681 + 26832400 = 7209^2 + 5180^2 .

It is a cyclic number.

It is not a de Polignac number, because 78802081 - 2¹⁷ = 78671009 is a prime.

It is a super-2 number, since 2×78802081² = 12419535939861122, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (78802051) 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, 59686 + ... + 60991.

It is an arithmetic number, because the mean of its divisors is an integer number (19730853).

Almost surely, 2^78802081 is an apocalyptic number.

It is an amenable number.

78802081 is a deficient number, since it is larger than the sum of its proper divisors (121331).

78802081 is a wasteful number, since it uses less digits than its factorization.

78802081 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 121330.

The product of its (nonzero) digits is 7168, while the sum is 34.

The square root of 78802081 is about 8877.0536215571. The cubic root of 78802081 is about 428.7254144175.

It can be divided in two parts, 7 and 8802081, that added together give a palindrome (8802088).

The spelling of 78802081 in words is "seventy-eight million, eight hundred two thousand, eighty-one".