78161664 has 216 divisors, whose sum is σ = 253521408. Its totient is φ = 21288960.

The previous prime is 78161647. The next prime is 78161683. The reversal of 78161664 is 46616187.

It is a happy number.

It is a super-2 number, since 2×78161664² = 12218491438497792, which contains 22 as substring.

It is a nude number because it is divisible by every one of its digits.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 1166559 + ... + 1166625.

Almost surely, 2^78161664 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 78161664, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (126760704).

78161664 is an abundant number, since it is smaller than the sum of its proper divisors (175359744).

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

78161664 is a wasteful number, since it uses less digits than its factorization.

78161664 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 131 (or 110 counting only the distinct ones).

The product of its digits is 48384, while the sum is 39.

The square root of 78161664 is about 8840.9085505959. The cubic root of 78161664 is about 427.5608504059.

The spelling of 78161664 in words is "seventy-eight million, one hundred sixty-one thousand, six hundred sixty-four".