78174913 has 2 divisors, whose sum is σ = 78174914. Its totient is φ = 78174912.

The previous prime is 78174883. The next prime is 78174917. The reversal of 78174913 is 31947187.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 44395569 + 33779344 = 6663^2 + 5812^2 .

It is an emirp because it is prime and its reverse (31947187) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 78174913 - 2²⁵ = 44620481 is a prime.

It is a super-2 number, since 2×78174913² = 12222634045115138, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (78174917) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 39087456 + 39087457.

It is an arithmetic number, because the mean of its divisors is an integer number (39087457).

Almost surely, 2^78174913 is an apocalyptic number.

It is an amenable number.

78174913 is a deficient number, since it is larger than the sum of its proper divisors (1).

78174913 is an equidigital number, since it uses as much as digits as its factorization.

78174913 is an evil number, because the sum of its binary digits is even.

The product of its digits is 42336, while the sum is 40.

The square root of 78174913 is about 8841.6578196626. The cubic root of 78174913 is about 427.5850073194.

The spelling of 78174913 in words is "seventy-eight million, one hundred seventy-four thousand, nine hundred thirteen".