71920405 has 8 divisors (see below), whose sum is σ = 86714784. Its totient is φ = 57262800.

The previous prime is 71920367. The next prime is 71920411. The reversal of 71920405 is 50402917.

It is a happy number.

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

It is a de Polignac number, because none of the positive numbers 2^k-71920405 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 33031 + ... + 35140.

It is an arithmetic number, because the mean of its divisors is an integer number (10839348).

Almost surely, 2^71920405 is an apocalyptic number.

It is an amenable number.

71920405 is a deficient number, since it is larger than the sum of its proper divisors (14794379).

71920405 is a wasteful number, since it uses less digits than its factorization.

71920405 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 68387.

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

The square root of 71920405 is about 8480.5898969352. The cubic root of 71920405 is about 415.8634078335.

The spelling of 71920405 in words is "seventy-one million, nine hundred twenty thousand, four hundred five".