78055381 has 4 divisors (see below), whose sum is σ = 82646892. Its totient is φ = 73463872.

The previous prime is 78055301. The next prime is 78055409. The reversal of 78055381 is 18355087.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 18355087 = 17 ⋅1079711.

It can be written as a sum of positive squares in 2 ways, for example, as 70711281 + 7344100 = 8409^2 + 2710^2 .

It is a cyclic number.

It is not a de Polignac number, because 78055381 - 2¹¹ = 78053333 is a prime.

It is a super-2 number, since 2×78055381² = 12185285006110322, 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 78055381.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (78055301) 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, 2295730 + ... + 2295763.

It is an arithmetic number, because the mean of its divisors is an integer number (20661723).

Almost surely, 2^78055381 is an apocalyptic number.

It is an amenable number.

78055381 is a deficient number, since it is larger than the sum of its proper divisors (4591511).

78055381 is a wasteful number, since it uses less digits than its factorization.

78055381 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4591510.

The product of its (nonzero) digits is 33600, while the sum is 37.

The square root of 78055381 is about 8834.8956417153. The cubic root of 78055381 is about 427.3669656614.

The spelling of 78055381 in words is "seventy-eight million, fifty-five thousand, three hundred eighty-one".