78475121 has 4 divisors (see below), whose sum is σ = 78511092. Its totient is φ = 78439152.

The previous prime is 78475087. The next prime is 78475123. The reversal of 78475121 is 12157487.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 12157487 = 31 ⋅392177.

It can be written as a sum of positive squares in 2 ways, for example, as 14714896 + 63760225 = 3836^2 + 7985^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-78475121 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (78475123) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 14486 + ... + 19151.

It is an arithmetic number, because the mean of its divisors is an integer number (19627773).

Almost surely, 2^78475121 is an apocalyptic number.

It is an amenable number.

78475121 is a deficient number, since it is larger than the sum of its proper divisors (35971).

78475121 is a wasteful number, since it uses less digits than its factorization.

78475121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 35970.

The product of its digits is 15680, while the sum is 35.

The square root of 78475121 is about 8858.6184588795. The cubic root of 78475121 is about 428.1316467684.

The spelling of 78475121 in words is "seventy-eight million, four hundred seventy-five thousand, one hundred twenty-one".