78406144 has 20 divisors (see below), whose sum is σ = 156660174. Its totient is φ = 39202816.

The previous prime is 78406121. The next prime is 78406151. The reversal of 78406144 is 44160487.

It can be written as a sum of positive squares in only one way, i.e., 42406144 + 36000000 = 6512^2 + 6000^2 .

It is a super-2 number, since 2×78406144² = 12295046833897472, which contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 76057 + ... + 77080.

Almost surely, 2^78406144 is an apocalyptic number.

It is an amenable number.

78406144 is a deficient number, since it is larger than the sum of its proper divisors (78254030).

78406144 is an equidigital number, since it uses as much as digits as its factorization.

78406144 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 153155 (or 153139 counting only the distinct ones).

The product of its (nonzero) digits is 21504, while the sum is 34.

The square root of 78406144 is about 8854.7243887091. The cubic root of 78406144 is about 428.0061722113.

The spelling of 78406144 in words is "seventy-eight million, four hundred six thousand, one hundred forty-four".