78181870 has 32 divisors (see below), whose sum is σ = 154052640. Its totient is φ = 28391040.

The previous prime is 78181867. The next prime is 78181879. The reversal of 78181870 is 7818187.

It is a super-2 number, since 2×78181870² = 12224809593393800, which contains 22 as substring.

It is an alternating number because its digits alternate between odd and even.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (78181879) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 3001 + ... + 12859.

It is an arithmetic number, because the mean of its divisors is an integer number (4814145).

Almost surely, 2^78181870 is an apocalyptic number.

78181870 is a deficient number, since it is larger than the sum of its proper divisors (75870770).

78181870 is a wasteful number, since it uses less digits than its factorization.

78181870 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9940.

The product of its (nonzero) digits is 25088, while the sum is 40.

The square root of 78181870 is about 8842.0512326043. The cubic root of 78181870 is about 427.5976909308.

The spelling of 78181870 in words is "seventy-eight million, one hundred eighty-one thousand, eight hundred seventy".