78120457 has 24 divisors (see below), whose sum is σ = 89742240. Its totient is φ = 67760640.

The previous prime is 78120451. The next prime is 78120467. The reversal of 78120457 is 75402187.

It is a happy number.

It is not a de Polignac number, because 78120457 - 2¹⁵ = 78087689 is a prime.

It is a super-2 number, since 2×78120457² = 12205611603777698, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (78120451) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 224958 + ... + 225304.

It is an arithmetic number, because the mean of its divisors is an integer number (3739260).

Almost surely, 2^78120457 is an apocalyptic number.

It is an amenable number.

78120457 is a deficient number, since it is larger than the sum of its proper divisors (11621783).

78120457 is a wasteful number, since it uses less digits than its factorization.

78120457 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 441 (or 424 counting only the distinct ones).

The product of its (nonzero) digits is 15680, while the sum is 34.

The square root of 78120457 is about 8838.5777702072. The cubic root of 78120457 is about 427.4857001931.

The spelling of 78120457 in words is "seventy-eight million, one hundred twenty thousand, four hundred fifty-seven".