71920399 has 4 divisors (see below), whose sum is σ = 72243136. Its totient is φ = 71597664.

The previous prime is 71920367. The next prime is 71920411. The reversal of 71920399 is 99302917.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 71920399 - 2⁵ = 71920367 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 (71920349) 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, 161034 + ... + 161479.

It is an arithmetic number, because the mean of its divisors is an integer number (18060784).

Almost surely, 2^71920399 is an apocalyptic number.

71920399 is a deficient number, since it is larger than the sum of its proper divisors (322737).

71920399 is a wasteful number, since it uses less digits than its factorization.

71920399 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 322736.

The product of its (nonzero) digits is 30618, while the sum is 40.

The square root of 71920399 is about 8480.5895431863. The cubic root of 71920399 is about 415.8633962689.

The spelling of 71920399 in words is "seventy-one million, nine hundred twenty thousand, three hundred ninety-nine".