71984399 has 4 divisors (see below), whose sum is σ = 72147336. Its totient is φ = 71821464.

The previous prime is 71984389. The next prime is 71984413. The reversal of 71984399 is 99348917.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 99348917 = 1361 ⋅72997.

It is a cyclic number.

It is not a de Polignac number, because 71984399 - 2²⁴ = 55207183 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (71984329) 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, 80804 + ... + 81689.

It is an arithmetic number, because the mean of its divisors is an integer number (18036834).

Almost surely, 2^71984399 is an apocalyptic number.

71984399 is a deficient number, since it is larger than the sum of its proper divisors (162937).

71984399 is a wasteful number, since it uses less digits than its factorization.

71984399 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 162936.

The product of its digits is 489888, while the sum is 50.

The square root of 71984399 is about 8484.3620266936. The cubic root of 71984399 is about 415.9867148587.

The spelling of 71984399 in words is "seventy-one million, nine hundred eighty-four thousand, three hundred ninety-nine".