71920217 has 8 divisors (see below), whose sum is σ = 78607872. Its totient is φ = 65505600.

The previous prime is 71920213. The next prime is 71920229. The reversal of 71920217 is 71202917.

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

It is a cyclic number.

It is not a de Polignac number, because 71920217 - 2² = 71920213 is a prime.

It is a super-2 number, since 2×71920217² = 10345035226654178, which contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 71920217.

It is not an unprimeable number, because it can be changed into a prime (71920213) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 67709 + ... + 68762.

It is an arithmetic number, because the mean of its divisors is an integer number (9825984).

Almost surely, 2^71920217 is an apocalyptic number.

It is an amenable number.

71920217 is a deficient number, since it is larger than the sum of its proper divisors (6687655).

71920217 is a wasteful number, since it uses less digits than its factorization.

71920217 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 136519.

The product of its (nonzero) digits is 1764, while the sum is 29.

The square root of 71920217 is about 8480.5788127934. The cubic root of 71920217 is about 415.8630454774.

The spelling of 71920217 in words is "seventy-one million, nine hundred twenty thousand, two hundred seventeen".