67978513 has 4 divisors (see below), whose sum is σ = 68038128. Its totient is φ = 67918900.

The previous prime is 67978511. The next prime is 67978543. The reversal of 67978513 is 31587976.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 67978513 - 2¹ = 67978511 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (67978511) 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, 28063 + ... + 30388.

It is an arithmetic number, because the mean of its divisors is an integer number (17009532).

Almost surely, 2^67978513 is an apocalyptic number.

It is an amenable number.

67978513 is a deficient number, since it is larger than the sum of its proper divisors (59615).

67978513 is a wasteful number, since it uses less digits than its factorization.

67978513 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 59614.

The product of its digits is 317520, while the sum is 46.

The square root of 67978513 is about 8244.9083075556. The cubic root of 67978513 is about 408.1225142298.

The spelling of 67978513 in words is "sixty-seven million, nine hundred seventy-eight thousand, five hundred thirteen".