78389478 has 32 divisors (see below), whose sum is σ = 183369600. Its totient is φ = 24754248.

The previous prime is 78389449. The next prime is 78389501. The reversal of 78389478 is 87498387.

It is a super-2 number, since 2×78389478² = 12289820522224968, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (54).

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

It is a congruent number.

It is an unprimeable number.

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 15 ways as a sum of consecutive naturals, for example, 37176 + ... + 39227.

It is an arithmetic number, because the mean of its divisors is an integer number (5730300).

Almost surely, 2^78389478 is an apocalyptic number.

78389478 is an abundant number, since it is smaller than the sum of its proper divisors (104980122).

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

78389478 is a wasteful number, since it uses less digits than its factorization.

78389478 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 76433 (or 76427 counting only the distinct ones).

The product of its digits is 2709504, while the sum is 54.

The square root of 78389478 is about 8853.7832591497. The cubic root of 78389478 is about 427.9758444166.

The spelling of 78389478 in words is "seventy-eight million, three hundred eighty-nine thousand, four hundred seventy-eight".