71221249 has 4 divisors (see below), whose sum is σ = 77695920. Its totient is φ = 64746580.

The previous prime is 71221217. The next prime is 71221259. The reversal of 71221249 is 94212217.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 71221249 - 2⁵ = 71221217 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (71221259) 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, 3237319 + ... + 3237340.

It is an arithmetic number, because the mean of its divisors is an integer number (19423980).

It is a Proth number, since it is equal to 4347 ⋅ 2¹⁴ + 1 and 4347 < 2¹⁴.

Almost surely, 2^71221249 is an apocalyptic number.

It is an amenable number.

71221249 is a deficient number, since it is larger than the sum of its proper divisors (6474671).

71221249 is a wasteful number, since it uses less digits than its factorization.

71221249 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6474670.

The product of its digits is 2016, while the sum is 28.

The square root of 71221249 is about 8439.2682739678. The cubic root of 71221249 is about 414.5114471480.

The spelling of 71221249 in words is "seventy-one million, two hundred twenty-one thousand, two hundred forty-nine".