78394644 has 36 divisors (see below), whose sum is σ = 198487744. Its totient is φ = 26088912.

The previous prime is 78394619. The next prime is 78394651. The reversal of 78394644 is 44649387.

It is a tau number, because it is divible by the number of its divisors (36).

It is a super-2 number, since 2×78394644² = 12291440415773472, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 78394644.

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 11 ways as a sum of consecutive naturals, for example, 26949 + ... + 29715.

Almost surely, 2^78394644 is an apocalyptic number.

It is an amenable number.

78394644 is an abundant number, since it is smaller than the sum of its proper divisors (120093100).

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

78394644 is a wasteful number, since it uses less digits than its factorization.

78394644 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3564 (or 3559 counting only the distinct ones).

The product of its digits is 580608, while the sum is 45.

The square root of 78394644 is about 8854.0749940352. The cubic root of 78394644 is about 427.9852456555.

The spelling of 78394644 in words is "seventy-eight million, three hundred ninety-four thousand, six hundred forty-four".