78643437 has 8 divisors (see below), whose sum is σ = 105030336. Its totient is φ = 52342752.

The previous prime is 78643393. The next prime is 78643507. The reversal of 78643437 is 73434687.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 78643437 - 2¹⁰ = 78642413 is a prime.

It is a Smith number, since the sum of its digits (42) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (78643237) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 19393 + ... + 23094.

It is an arithmetic number, because the mean of its divisors is an integer number (13128792).

Almost surely, 2^78643437 is an apocalyptic number.

It is an amenable number.

78643437 is a deficient number, since it is larger than the sum of its proper divisors (26386899).

78643437 is a wasteful number, since it uses less digits than its factorization.

78643437 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 43107.

The product of its digits is 338688, while the sum is 42.

The square root of 78643437 is about 8868.1134972439. The cubic root of 78643437 is about 428.4375184330.

The spelling of 78643437 in words is "seventy-eight million, six hundred forty-three thousand, four hundred thirty-seven".