78204638 has 8 divisors (see below), whose sum is σ = 117740640. Its totient is φ = 38957760.

The previous prime is 78204631. The next prime is 78204653. The reversal of 78204638 is 83640287.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a super-2 number, since 2×78204638² = 12231930809422088, which contains 22 as substring.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (78204631) 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, 71603 + ... + 72686.

It is an arithmetic number, because the mean of its divisors is an integer number (14717580).

Almost surely, 2^78204638 is an apocalyptic number.

78204638 is a deficient number, since it is larger than the sum of its proper divisors (39536002).

78204638 is a wasteful number, since it uses less digits than its factorization.

78204638 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 144562.

The product of its (nonzero) digits is 64512, while the sum is 38.

The square root of 78204638 is about 8843.3386229410. The cubic root of 78204638 is about 427.6391950089.

The spelling of 78204638 in words is "seventy-eight million, two hundred four thousand, six hundred thirty-eight".