78538881 has 4 divisors (see below), whose sum is σ = 104718512. Its totient is φ = 52359252.

The previous prime is 78538849. The next prime is 78538891. The reversal of 78538881 is 18883587.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 78538881 - 2⁵ = 78538849 is a prime.

It is a super-2 number, since 2×78538881² = 12336711657464322, which contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 78538881.

It is not an unprimeable number, because it can be changed into a prime (78538891) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 13089811 + ... + 13089816.

It is an arithmetic number, because the mean of its divisors is an integer number (26179628).

Almost surely, 2^78538881 is an apocalyptic number.

It is an amenable number.

78538881 is a deficient number, since it is larger than the sum of its proper divisors (26179631).

78538881 is a wasteful number, since it uses less digits than its factorization.

78538881 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 26179630.

The product of its digits is 430080, while the sum is 48.

The square root of 78538881 is about 8862.2164834764. The cubic root of 78538881 is about 428.2475658172.

The spelling of 78538881 in words is "seventy-eight million, five hundred thirty-eight thousand, eight hundred eighty-one".