78161400 has 144 divisors (see below), whose sum is σ = 265061160. Its totient is φ = 20640000.

The previous prime is 78161399. The next prime is 78161407. The reversal of 78161400 is 416187.

It is a happy number.

It is a super-2 number, since 2×78161400² = 12218408899920000, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (78161407) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 311275 + ... + 311525.

Almost surely, 2^78161400 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 78161400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (132530580).

78161400 is an abundant number, since it is smaller than the sum of its proper divisors (186899760).

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

78161400 is a wasteful number, since it uses less digits than its factorization.

78161400 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 446 (or 434 counting only the distinct ones).

The product of its (nonzero) digits is 1344, while the sum is 27.

The square root of 78161400 is about 8840.8936199911. The cubic root of 78161400 is about 427.5603690267.

Adding to 78161400 its reverse (416187), we get a palindrome (78577587).

It can be divided in two parts, 7816 and 1400, that added together give a square (9216 = 96²).

The spelling of 78161400 in words is "seventy-eight million, one hundred sixty-one thousand, four hundred".