78388422 has 64 divisors (see below), whose sum is σ = 186806784. Its totient is φ = 21461760.

The previous prime is 78388417. The next prime is 78388447. The reversal of 78388422 is 22488387.

It is a super-2 number, since 2×78388422² = 12289489407300168, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (42).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 113097 + ... + 113787.

It is an arithmetic number, because the mean of its divisors is an integer number (2918856).

Almost surely, 2^78388422 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 78388422, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (93403392).

78388422 is an abundant number, since it is smaller than the sum of its proper divisors (108418362).

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

78388422 is a wasteful number, since it uses less digits than its factorization.

78388422 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 813.

The product of its digits is 172032, while the sum is 42.

The square root of 78388422 is about 8853.7236234253. The cubic root of 78388422 is about 427.9739226258.

The spelling of 78388422 in words is "seventy-eight million, three hundred eighty-eight thousand, four hundred twenty-two".