78193649 has 4 divisors (see below), whose sum is σ = 79295040. Its totient is φ = 77092260.

The previous prime is 78193631. The next prime is 78193673. The reversal of 78193649 is 94639187.

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 a de Polignac number, because none of the positive numbers 2^k-78193649 is a prime.

It is a super-2 number, since 2×78193649² = 12228493487870402, which contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (78193679) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 550589 + ... + 550730.

It is an arithmetic number, because the mean of its divisors is an integer number (19823760).

Almost surely, 2^78193649 is an apocalyptic number.

It is an amenable number.

78193649 is a deficient number, since it is larger than the sum of its proper divisors (1101391).

78193649 is a wasteful number, since it uses less digits than its factorization.

78193649 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1101390.

The product of its digits is 326592, while the sum is 47.

The square root of 78193649 is about 8842.7172859930. The cubic root of 78193649 is about 427.6191640263.

The spelling of 78193649 in words is "seventy-eight million, one hundred ninety-three thousand, six hundred forty-nine".