78234138 has 12 divisors (see below), whose sum is σ = 169507338. Its totient is φ = 26078040.

The previous prime is 78234137. The next prime is 78234181. The reversal of 78234138 is 83143287.

It can be written as a sum of positive squares in only one way, i.e., 67125249 + 11108889 = 8193^2 + 3333^2 .

It is a super-2 number, since 2×78234138² = 12241160697206088, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (78234131) 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 5 ways as a sum of consecutive naturals, for example, 2173153 + ... + 2173188.

Almost surely, 2^78234138 is an apocalyptic number.

78234138 is an abundant number, since it is smaller than the sum of its proper divisors (91273200).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

78234138 is a wasteful number, since it uses less digits than its factorization.

78234138 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4346349 (or 4346346 counting only the distinct ones).

The product of its digits is 32256, while the sum is 36.

The square root of 78234138 is about 8845.0063877874. The cubic root of 78234138 is about 427.6929589572.

The spelling of 78234138 in words is "seventy-eight million, two hundred thirty-four thousand, one hundred thirty-eight".