71920045 has 8 divisors (see below), whose sum is σ = 88636824. Its totient is φ = 55980864.

The previous prime is 71920039. The next prime is 71920061. The reversal of 71920045 is 54002917.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 27910089 + 44009956 = 5283^2 + 6634^2 .

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-71920045 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 71919995 and 71920022.

It is a congruent number.

It is an unprimeable number.

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 7 ways as a sum of consecutive naturals, for example, 194194 + ... + 194563.

It is an arithmetic number, because the mean of its divisors is an integer number (11079603).

Almost surely, 2^71920045 is an apocalyptic number.

It is an amenable number.

71920045 is a deficient number, since it is larger than the sum of its proper divisors (16716779).

71920045 is a wasteful number, since it uses less digits than its factorization.

71920045 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 388799.

The product of its (nonzero) digits is 2520, while the sum is 28.

The square root of 71920045 is about 8480.5686719701. The cubic root of 71920045 is about 415.8627139596.

The spelling of 71920045 in words is "seventy-one million, nine hundred twenty thousand, forty-five".