78143871 has 16 divisors (see below), whose sum is σ = 112484736. Its totient is φ = 47969376.

The previous prime is 78143861. The next prime is 78143911. The reversal of 78143871 is 17834187.

It is not a de Polignac number, because 78143871 - 2¹⁷ = 78012799 is a prime.

It is a super-2 number, since 2×78143871² = 12212929149729282, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (39).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (78143851) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 15016 + ... + 19538.

It is an arithmetic number, because the mean of its divisors is an integer number (7030296).

Almost surely, 2^78143871 is an apocalyptic number.

78143871 is a deficient number, since it is larger than the sum of its proper divisors (34340865).

78143871 is a wasteful number, since it uses less digits than its factorization.

78143871 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4982.

The product of its digits is 37632, while the sum is 39.

The square root of 78143871 is about 8839.9022053414. The cubic root of 78143871 is about 427.5284041180.

The spelling of 78143871 in words is "seventy-eight million, one hundred forty-three thousand, eight hundred seventy-one".